Mammalian prestin

ABSTRACT

The invention relates to mammalian prestin protein, which has been discovered to be the mammalian cochlear outer hair cell motor, and to polynucleotides encoding prestin. Full length gerbil prestin and its cDNA are described, full length murine prestin and its cDNA are described, and a partial sequence of human prestin and its chromosomal location are described.

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority under 35 U.S.C. §119(c) to U.S. Provisional Application No. 60/183,461, filed on Feb. 19, 2000.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] The invention was made in part using funds obtained from the U.S. Government (National Institutes of Health Grant No. DC00708) and the U.S. government may have certain rights in the invention.

BACKGROUND OF THE INVENTION

[0003] The mammalian cochlea has two types of hair cells. Cochlear hair cells are non-neuronal epithelial cells that transduce acoustic signals. Outer hair cells (OHCs) are responsible for the exquisite sensitivity and frequency-resolving capacity of the normal mammalian hearing organ, the ear; they provide local mechanical amplification (the “cochlear amplifier”) in the form of feedback (1987, Ashmore, et al., J. Physiol. (London), 388:323-347). In contrast, inner hair cells (IHCs) convey auditory information to the brain (Dallos, P., Overview: Cochlear Neurobiology, pages 1-43, Springer, NY, 1996). OHCs have cylindrical somata of constant diameter and variable length. It is generally believed that the mammalian cochlea owes its remarkable sensitivity, frequency selectivity, and various complex nonlinear properties to a mechanical feedback action by OHCs.

[0004] In response to membrane potential change, the OHC rapidly alters its length and stiffness (1985, Brownell et al., Science, 227:194-196). These mechanical changes, driven by putative molecular motors, are assumed to produce amplification of vibrations in the cochlea that are transduced by IHCs. These somatic shape changes may be up to 5% of the cell length; The cell shortens when depolarized and lengthens when hyperpolarized. Length changes do not depend on either ATP or Ca²⁺ (1988, Holley et al., Proc. R. Soc. Lond. Ser. B. Biol. Sci., 232:413-429.) and they can be elicited with unchanging amplitude at microsecond rates up to high audio frequencies. Motile responses are accompanied by charge movement, reflected in nonlinear capacitance, akin to the translocation of gating charges of voltage-gated ion channels (1991, Santos-Sacchi et al., J. Neurosci., 11:3096-3110). This nonlinear capacitance is widely used as a “signature” of the electromotile process. Motility is also accompanied by axial stiffness change of the cell. By virtually any test, electromotility and electrically-induced stiffness changes can be correlated with each other and they are collectively described as voltage-dependent mechanical changes of the OHC, heretofore called electromechanics. These observations make it apparent that the fast mechanical changes in OHCs are powered by a novel molecular motor, fundamentally different from other biological force generators, such as the myosin, kinesin or dynein families. The OHC molecular motor performs direct, rapid, reversible electromechanical conversion.

[0005] Despite extensive studies of cellular and biophysical mechanisms of OHC function, very little is known about the genes and molecular events involved in OHC function. OHC electromotility is the likely result of the concerted action of a large number of independent molecular motors that are closely associated with the cell's basolateral membrane, possibly by the densely packed 10 nanometer particles seen therein.

[0006] There have been some suggestions as to the identity of these motor molecules. Based on similarities between the cortical structure of erythrocytes and OHCs, it has been proposed that the motor molecule is a modified anion exchanger. Because their shallow voltage dependence matches that of charge movement in OHCs, transporters have been favored, as opposed to modified voltage-dependent channels, as likely candidates. A recent suggestion is that the motor is related to a fructose transporter, GLUTS. Until the present invention, molecular identification of the motor protein has not been achieved.

SUMMARY OF THE INVENTION

[0007] The invention includes an isolated polynucleotide comprising a portion that anneals with high stringency with at least twenty consecutive nucleotide residues of a coding region of a mammalian pres gene.

[0008] In one aspect, the mammalian pres gene comprises a nucleotide sequence listed in SEQ ID NO: 2 or SEQ ID NO: 4.

[0009] In another aspect, the coding region is one other than a coding region corresponding to any of exons 1-6 of the human pres gene.

[0010] The invention also includes an isolated polynucleotide comprising the coding regions of a mammalian prestin gene, wherein the coding regions of the prestin gene are at least 75% homologous with the coding region of at least one of the gerbil and murine prestin gene.

[0011] In a preferred aspect, the isolated polynucleotide comprises a promoter/regulatory region operably linked with the coding regions.

[0012] An isolated mammalian prestin protein is also encompassed by the invention. In one aspect, the mammalian prestin protein is isolated from a gerbil, a mouse, or a human. In another aspect, the protein has an amino acid sequence listed in SEQ ID NO: 1 or SEQ ID NO: 3. Preferably, the protein is substantially purified.

[0013] Also contemplated by the invention is an isolated antibody which binds specifically with a mammalian prestin protein.

[0014] The invention includes a method of alleviating a hearing disorder in a mammal afflicted with the disorder comprising providing a mammalian prestin protein to cochlear outer hair cells of the mammal, thereby alleviating the disorder. In one aspect, the protein is provided to the outer hair cells by providing a nucleic acid vector comprising a polynucleotide encoding the protein to the outer hair cells.

[0015] A method of rendering the surface area of a lipid bilayer susceptible to modulation by membrane potential is also envisaged in the invention. The method comprises providing a mammalian prestin protein to the bilayer, whereby the bilayer is rendered susceptible to modulation by membrane potential. In an aspect of the invention, the lipid bilayer is the plasma membrane of a cell.

[0016] In another aspect, the protein is provided to the lipid bilayer by providing an expressible nucleic acid vector comprising a polynucleotide encoding the protein to the cell and then expressing the protein in the cell.

[0017] The invention also includes a method of modulating the surface area of a lipid bilayer. The method comprises providing a mammalian prestin protein to the bilayer and modulating the membrane potential, thus modulating the surface area of the bilayer.

[0018] A method for modulating stiffness of a lipid bilyer surrounding a relatively fixed volume is also within the scope of the invention. The method comprises providing a mammalian prestin protein to the bilayer, modulating the membrane potential, and thus, modulating bilayer stiffness.

[0019] The invention also encompasses a method of modulating the volume of a porous bilammelar lipid vesicle. The method comprises providing a mammalian prestin protein to the bilayer and modulating the membrane potential, thereby modulating the volume of the vesicle.

[0020] The invention further includes a method for generating a force between two surfaces. The method comprises interposing a structure having a lipid membrane comprising prestin and enclosing a relatively fixed volume of fluid between the surfaces, restraining the ability of the structure to expand in a direction at least partially parallel to at least one of the surfaces, and altering the membrane potential of the lipid membrane. The structure impacts upon the two surfaces and a force is generated between them.

[0021] The invention also describes a method for generating an electrical impulse by applying a mechanical force to the prestin protein. The method comprises applying a mechanical stress on the prestin protein, such that the protein creates an electrical impulse in response to the mechanical force.

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The foregoing summary, as well as the following detailed description of the invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there are shown in the drawings embodiment(s) which are presently preferred. However, it should be understood that the invention is not limited to the precise arrangements and instrumentalities shown. In the drawings:

[0023]FIG. 1, comprising FIGS. 1A-1D, is a quartet of images depicting the results of subtractive hybridization experiments. Identical cDNA was fixed to each of the 4 blots and separately hybridized with radioactive probes. FIG. 1A represents forward-subtracted probe (OHC-IHC). FIG. 1B represents reverse-subtracted probe (IHC-OHC). FIG. 1C represents OHC probe, and FIG. 1D represents IHC probe. A signal comparison between OHC or OHC-IHC hybridization and IHC or IHC-OHC hybridization is indicated by the arrows.

[0024]FIG. 2 depicts the amino acid sequence of gerbil prestin (upper row), GenBank Accession Number AF230376 and SEQ ID NO: 1, and rat pendrin (lower row), GenBank Accession Number AF167412 (SEQ ID NO: 11). Bolded and underlined residues indicate the differences between the deduced human prestin sequence. Identical residues are indicated with an asterisk (*), while highly similar amino acids are indicated with a solid circle (). The sulfate transport motif is boxed with a solid line ( ). The positive charge cluster is outlined by a dotted line ( ), and the negative charge cluster is boxed with a dashed line ( ).

[0025]FIG. 3, comprising FIGS. 3A and 3B, lists the alignment of various sulfate transport motifs in selected proteins. FIG. 3A aligns prestin, pendrin, down-regulated in adenoma (DRA), and distrophic dysplasia (DTD) sequences from human and rodent species. Divergent residues in the prestin sequences are bolded. Amino acid residue numbers refer to gerbil prestin. FIG. 3B depicts sulfate transport motifs in a variety of putative transporters in lower organisms. Invariant residues are indicated with asterisks. The sulfate transport motif is defined by PROSITE PS01130.

[0026]FIG. 4, comprising FIGS. 4A-4D, represents an analysis of pres gene expression. FIG. 4A is a virtual Northern blot analysis of cDNA pools derived from mRNA of gerbil tissues hybridized with a [³²P]-labeled pres probe. FIG. 4B depicts PCR results where cDNA pools from different tissues were amplified with pres-specific and cyclophilin-specific primers. In FIGS. 4A and 4B, cochlea was derived from the organ of Corti. FIG. 4C is also a virtual Northern blot analysis. cDNA pools derived from the organ of Corti mRNA at 0, 6, 12, 16, and 20 days after birth (DAB) were hybridized with a [³²P]-labeled pres-specific probe, followed by stripping and rehybridization with a [³²P]-labeled cyclophilin probe. FIG. 4D indicates PCR results from the cDNA in FIG. 4C, amplified with pres and cyclophilin-specific primers.

[0027]FIG. 5, comprising FIGS. 5A-5D, depicts the voltage-dependent charge movement in TSA201 cells. All recordings were within 24-60 hours of transfection. FIG. 5A illustrates the charge movement measured as transient capacitive currents using a standar subraction technique (P/4). The cell is held at −70 millivolts and voltage steps are 20 millivolts to +50 millivolts. FIG. 5B is a stair-step protocol quantifying voltage dependence of nonlinear capacitance of 20 presentations which were averaged. Voltage was increased from −130 millivolts to +40 millivolts in 10 millivolt increments. FIG. 5C illustrates the membrane capacitance-voltage curve obtained from the stair-step current trace in FIG. 5B. The trace fits data points with a derivative of a Boltzmann function. FIG. 5D demonstrates that localized application of 10 millimolar sodium salicylate reversibly blocks charge movement.

[0028]FIG. 6, comprising FIGS. 6A-6E, depicts examples of voltage-dependent motility expressed in TSA201 cells. FIG. 6A is an image of a TSA201 cell being partially drawn in to a microchamber. FIG. 6B is a trace representing motile responses from control and transfected cells. The top two traces depict motile responses for the transfected cells, while the bottom trace depicts lack of motile response for the control cell. FIG. 6C demonstrates the effect of 10 millimolar sodium salicylate in the external bathing solution on the motile response. FIG. 6D depicts response (top) and stimulus (bottom) waveforms with two different command frequencies. FIG. 6E illustrates Fourier transforms of the response segments in FIG. 6D (top). A 1.2 decibel correction for frequency response was incorporated into the resultant Fourier transforms in FIG. 6E. Response waveforms are the average of 200 presentations.

[0029]FIG. 7, comprising FIGS. 7A and 7B, lists the gerbil cDNA sequence encoding prestin (SEQ ID NO: 2).

[0030]FIG. 8, comprising FIGS. 8A, 8B, and 8C lists a portion of the nucleotide sequence (SEQ ID NO: 2) and the amino acid sequence of gerbil prestin (SEQ ID NO: 1) with the corresponding human amino acid sequence beneath it (SEQ ID NO: 5).

[0031]FIG. 9, comprising FIGS. 9A-9M, lists a portion of the nucleic acid sequence of BAC clone RG107G13 (GenBank Accession Number RG107G13; SEQ ID NO: 6) from nucleotide residue number 90,000 to nucleotide residue number 119, 484.

[0032]FIG. 10, comprising FIGS. 10A and 10B, lists the murine cDNA sequence of prestin (FIG. 10A, SEQ ID NO: 4) and the murine amino acid sequence of prestin (FIG. 10B, SEQ ID NO: 3).

[0033]FIG. 11 is a schematic diagram depicting Stage 1 of the procedure for establishing the OHC subtracted library. After obtaining polyA RNA from each of the OHCs and IHCs, 5′-cap reverse transcription oligo-dT dependent PCR is preformed to obtain the cDNA pools of each of the OHCs and IHCs. After the hybridization screening, the cDNA can be reverse or forward subtracted or subtracted using tester or driver cDNA alone.

[0034]FIG. 12, comprising FIGS. 12A-12D, is a quartet of images depicting IHCs and OHCs isolated from adult gerbil cochlea. Note the differences in stereocilia configuration.

[0035]FIG. 13, comprising FIGS. 13A, 13B, and 13C, is a series of images depicting the typical whole-cell current responses recorded in OHCs (FIG. 13A) and IHCs (FIG. 13B). FIG. 13C depicts the same responses in graph form.

[0036]FIG. 14 is an image of an agarose gel stained with ethidium bromide. The image depicts subracted cDNA pools prior to cloning. Forward-subtracted cDNA is compared to unsubtracted cDNA.

[0037]FIG. 15 is an image depicting amplification and size determination of cloned OHC-subtracted cDNAs. These cDNAs were used for the hybridization screening analysis depicted in FIG. 16.

[0038]FIG. 16, comprising FIGS. 16A-16D, is a series of cDNA hybidization dot-blot assays. These blots demonstrate differential hybridization of the cloned, subtracted OHC cDNAs shown in FIG. 15. FIG. 16A represents a hybridization blot hybridized with radioactive forward subtracted (OHC-IHC) probe. FIG. 16B represents hybridization with radioactive reverse subtracted (IHC-OHC) probe. FIGS. 16C and 16D represent hybridization with radioactive tester (OHC) and driver (IHC) probes, respsectively.

[0039]FIG. 17 is a schematic diagram depicting Stage 2 of the procedure for analyzing an OHC subtracted library.

[0040]FIG. 18 is an image of a virtual Northern dot blot which confirms the differential expression of OHC-subtracted cDNAs.

[0041]FIG. 19, comprising FIGS. 19A and 19B, is a pair of images depicting immunofluorescent expression of C-terminal tagged pres in transfected TSA201 cells. FIG. 19A illustrates cells transfected with control vector and FIG. 19B demonstrates cells transfected with C-terminal tagged prestin.

[0042]FIG. 20 depicts the nonlinear capacitance of TSA201 cells transiently transfected with N-tagged prestin construct.

[0043]FIG. 21, comprising FIGS. 21A-21D, depicts immunofluorescence images of TSA201 cells transiently transfected with C-tagged prestin (V5 epitope; FIGS. 21A and 21C) and N-tagged prestin (Xpress epitope; FIGS. 21B and 21D). FIGS. 21A and 21B depict permeabilized cells and FIGS. 21C and 21D depict nonpermeabilized cells. C-tagged prestin magnification is 100×. N-tagged prestin magnification is 40×.

[0044]FIG. 22, comprising FIGS. 22A-22D, is a set of images depicting immunofluorescence of transiently transfected TSA201 cells. FIGS. 22A and 22B represent the identical cells transfected with C-tagged prestin, with different filters. Magnification at 40×. FIG. 22C and 22D represent identical cells viewed with different filters. Magnification at 20×. FIGS. 22A and 22C depict cells binding with FITC-labeled anti-rabbit IgG, indicating cells expressing native prestin FIGS. 22B and 22D depict cells binding with Cy3-conjugated mouse IgG, indicating cells expressing the V5 tag epitope.

[0045]FIG. 23, comprising FIGS. 23A-23D, is a set of immunofluorescent images of the basilar membrane/organ of Corti complex. FIGS. 23A and 23B depict images of the same cells, viewed through different filters at 20× magnification. FIGS. 23C and 23D depict images of the same cells viewed through different filters at 40× magnification. FIGS. 23A and 23C depict cells binding with FITC-labeled rabbit IgG, indicating cells expressing prestin. FIGS. 23B and 23D depict cells stained with propidium iodide, indicating location of the cell nuclei.

[0046]FIG. 24, comprising FIGS. 24A-24D, is a set of immunofluorescent images of permeabilized (FIGS. 24A and 24B) and nonpermeabilized (FIGS. 24C and 24D) cells binding with FITC-labeled rabbit IgG. FIGS. 24A and 24C are magnified 20× and FIGS. 24B and 24D are magnified 40×.

[0047]FIG. 25 represents a predicted topology of the prestin protein. Charge clusters and sulfate transporter motif are indicated by boxes.

DETAILED DESCRIPTION OF THE INVENTION

[0048] The invention relates to discovery of an integral membrane protein which modulates the shape of mammalian cochlear outer hair cells in response to the membrane potential of the plasma membrane of the cells. In as much as the most distinguishing feature of this novel molecular motor of the invention is its speed, it has been designated as “prestin”, from the musical notation presto. The gene (Prestin) coding for this protein is abbreviated “Pres”, herein.

[0049] The amino acid sequence (SEQ ID NO: 1) of gerbil prestin is listed in FIG. 2, and the nucleotide sequence (SEQ ID NO: 2) of a gerbil EDNA which encodes prestin is listed in FIG. 7. A portion of the human gene (herein designated the pres gene) encoding prestin has been sequenced as a part of the human chromosome 7 sequencing effort. This portion corresponds to at least nucleotide residues 99,895-113,558 of BAC clone RG107G13 (GenBank Accession number RG107G13). The nucleotide sequence of residue numbers 90,000 to 119,484 of this clone (SEQ ID NO: 6) is reproduced in FIG. 9. The portion of the amino acid sequence of human prestin (SEQ ID NO: 5) corresponding to the sequenced region is referred to in FIG. 2 and is listed below the corresponding gerbil prestin amino acid sequence (SEQ ID NO: 1) in FIG. 8. FIG. 19 depicts surface expression of C-tagged prestin in TSA201 cells which were transfected as described in that example. The amino acid sequence (SEQ ID NO: 3) of murine prestin and the nucleotide sequence (SEQ ID NO: 4) of a cDNA encoding it have been determined, and are listed in FIGS. 10B and 10A, respectively. Portions of the murine pres gene were reported by others in a BAC clone derived from murine chromosome 5. The nucleotide sequence of this BAC clone is listed in GenBank accession number AC023284.

[0050] The invention includes an isolated polynucleotide which anneals with high stringency with at least twenty consecutive nucleotide residues of at least one strand of a mammalian pres gene, (e.g. the human, murine, or gerbil pres gene), or with one strand having a nucleotide sequence comprising SEQ ID NO: 2 having naturally-occurring introns interposed therewithin, or a coding region thereof. Preferably, the isolated polynucleotide of the invention anneals with high stringency with at least 25, more preferably with at least 30, and even more preferably with at least 40, at least 50, or at least 100 consecutive nucleotide residues. In certain embodiments, the isolated polynucleotide of the invention has a length not greater than about 200 nucleotide residues, more preferably not greater than about 100 nucleotide residues, and even more preferably not greater than about 50, 40, or even 35 nucleotide residues.

[0051] The isolated polynucleotide of the invention preferably has a sequence that is substantially homologous with at least 20, 25, or 35 consecutive nucleotide residues of at least one strand of the mammalian pres gene. More preferably, the isolated polynucleotide of has a sequence completely homologous with at least 20, 25, or 35 consecutive nucleotide residues of at least one strand of the mammalian pres gene, and even more preferably with at least 20, 25, or 35 consecutive nucleotide residues of at least one strand of a DNA having the nucleotide sequence SEQ ID NO: 2 or SEQ ID NO: 4.

[0052] The isolated polynucleotide can be inserted into a gene vector in order to facilitate cloning, fusion protein production, or delivery of the polynucleotide to a cell (i.e. in vitro or in vivo) for the purpose of inducing or enhancing expression of pres in the cell or for the purpose of inhibiting or preventing expression of pres in the cell (e.g. using an antisense oligonucleotide which binds specifically with at least one strand of a portion of the pres gene). When the vector is intended for use to induce or enhance expression of pres in a cell, the vector includes one or more promoter/regulatory sequences which cause the gene to be expressed in the presence of the normal transcription and/or translation mechanism of the cell.

[0053] When the isolated polynucleotide of the invention is to be hybridized or annealed with a nucleic acid having a sequence wherein at least a portion is complementary to the isolated polynucleotide, the necessary degree of homology between the isolated polynucleotide and the at least one strand of pres is dependent on the length of the polynucleotide. It is well known in the art that, as the length of a polynucleotide increases, the degree of complementarity necessary to anneal the polynucleotide with another polynucleotide with high stringency decreases. Numerous methods, algorithms, computer programs, and the like are known whereby the skilled artisan may predict the stringency of binding between two polynucleotides (e.g. Suhai, Ed., 1992, Computational Methods in Genome Research, Plenum Press, New York; Swindell, Ed., 1997, Sequence Data Analysis Guidebook, Humana Press, New Jersey; Bishop, Ed., 1998, Guide to Human Genome Computing, Academic Press, New York). Any of these methods, etc., may be used by the skilled artisan, in light of the present disclosure, to design or select isolated polynucleotides of various lengths which will anneal with at least one strand of a human pres gene with high stringency. All such isolated polynucleotides are included within the invention.

[0054] When the isolated polynucleotide of the invention is to be used to express all or a portion of a mammalian (e.g. human, murine, or gerbil) prestin protein, either in vitro or in vivo, it is important that (i) the homology of the isolated polynucleotide of the pres gene (e.g. SEQ ID NO: 2) is such that the amino acid sequence encoded by the isolated polynucleotide is identical to the corresponding region of pres, (ii) the differences between the sequence of the isolated polynucleotide and the corresponding region of pres does not result in differences in the encoded amino acid sequence (i.e. any sequence difference in a coding region merely substitutes a codon encoding an amino acid in place of another codon encoding the same amino acid), or (iii) any differences in the encoded amino acid sequence between the isolated polynucleotide and the corresponding region of pres results only in one or more conservative amino acid substitutions, as described in greater detail elsewhere herein. The following Human Codon Table may be used to select or identify alternate codons which encode the same amino acid. Human Codon Table Amino Acid Codons Encoding the Amino Acid Alanine GCA GCC GCG GCU Cysteine UGC UGU Aspartic acid GAC GAU Glutamic acid GAA GAG Phenylalanine UUC UUU Glycine GGA GGC GGG GGU Histidine CAC CAU Isoleucine AUA AUC AUU Lysine AAA AAG Leucine UUA UUG CUA CUC CUG CUU Methionine AUG Asparagine AAC AAU Proline CCA CCC CCG CCU Glutamine CAA CAG Arginine AGA AGG CGA CGC CGG CGU Serine AGC AGU UCA UCC UCG UCU Threonine ACA ACC ACG ACU Valine GUA GUC GUG GUU Tryptophan UGG Tyrosine UAC UAU

[0055] In situations in which it is necessary or desirable to introduce nucleotide residue changes into a polynucleotide, or into a prestin protein or a portion thereof, a variety of well-known techniques may be used, such as site-specific mutagenesis. Site-specific mutagenesis, for example, allows production of mutants through the use of specific oligonucleotides which encode the sequence of the desired mutation, as well as a sufficient number of adjacent nucleotides, to provide a primer sequence of sufficient size and sequence complementarity to form a stable duplex on both sides of the nucleotide sequence to be altered (e.g. a codon). Typically, a primer of about 17 to 25 nucleotides in length is preferred, with about 5 to 10 residues on both sides of the junction of the sequence being altered. This technique typically employs a phage vector which exists in both a single stranded and double stranded form. Typical vectors useful in site-directed mutagenesis include vectors such as M13 phage. Such vectors are commercially available, and their use is well known in the art. Double stranded plasmids are also routinely employed in site-directed mutagenesis protocols, to eliminate the need to transfer the gene of interest from a plasmid to a phage vector. Site-directed mutagenesis is performed by first obtaining a single-stranded vector or dissociating the two strands of a double stranded vector which includes within its sequence a DNA sequence which comprises the desired site of mutagenesis. The oligonucleotide primer described above is annealed with the single-stranded vector, and subjected to DNA polymerization, in order to generate a mutation-bearing strand. A heteroduplex is formed between the mutation-bearing strand and either the original non-mutated strand of the double-stranded vector or an added or synthesized strand which is substantially complementary to the mutation-bearing strand. This heteroduplex is then used to transform appropriate cells, such as E. coli or cultured human cells, and clones are selected which comprise recombinant vectors bearing the mutated sequence arrangement. Preparation of sequence variants of the isolated polynucleotide of the invention using site-directed mutagenesis is provided merely as an example of a method of producing potentially such variants, and is not intended to be limiting, as there are other well-known methods for producing such variants. By way of example, recombinant vectors comprising or encoding the desired isolated polynucleotide may be treated with mutagenic agents, such as hydroxylamine, to obtain sequence variants.

[0056] The isolated polynucleotide of the invention may be single stranded or double-stranded, it being understood that a single-stranded form is the form referred to herein when annealing of the isolated polynucleotide of the invention with another nucleic acid is described.

[0057] The determination of percent identity between two nucleotide or amino acid sequences can be accomplished using a mathematical algorithm. For example, a mathematical algorithm useful for comparing two sequences is the algorithm of Karlin and Altschul (1990, Proc. Natl. Acad. Sci. USA 87:2264-2268), modified as in Karlin and Altschul (1993, Proc. Natl. Acad. Sci. USA 90:5873-5877). This algorithm is incorporated into the NBLAST and XBLAST programs of Altschul, et al. (1990, J. Mol. Biol. 215:403-410), and can be accessed, for example at the National Center for Biotechnology Information (NCBI) world wide web site having the universal resource locator “http://www.ncbi.nlm.nih.gov/BLAST/”. BLAST nucleotide searches can be performed with the NBLAST program (designated “blastn” at the NCBI web site), using the following parameters: gap penalty=5; gap extension penalty=2; mismatch penalty=3; match reward=1; expectation value 10.0; and word size=11 to obtain nucleotide sequences homologous to a nucleic acid described herein. BLAST protein searches can be performed with the XBLAST program (designated “blastn” at the NCBI web site) or the NCBI “blastp” program, using the following parameters: expectation value 10.0, BLOSUM62 scoring matrix to obtain amino acid sequences homologous to a protein molecule described herein. To obtain gapped alignments for comparison purposes, Gapped BLAST can be utilized as described in Altschul et al. (1997, Nucleic Acids Res. 25:3389-3402). Alternatively, PSI-Blast or PHI-Blast can be used to perform an iterated search which detects distant relationships between molecules (Id.) and relationships between molecules which share a common pattern. When utilizing BLAST, Gapped BLAST, PSI-Blast, and PHI-Blast programs, the default parameters of the respective programs (e.g., XBLAST and NBLAST) can be used. See http://www.ncbi.nlm.nih.gov.

[0058] The percent identity between two sequences can be determined using techniques similar to those described above, with or without allowing gaps. In calculating percent identity, typically exact matches are counted.

[0059] The invention also relates to an isolated prestin protein which has a sequence which is identical or highly homologous (e.g. 70%, 80%, 85%, 90%, 95%, 98%, or 99% or more homologous) with the amino acid sequence of gerbil prestin (SEQ ID NO: 1) or murine prestin (SEQ ID NO: 3). Preferably, the isolated prestin protein is substantially purified. The isolated prestin protein may be in the form of a suspension of the native or denatured protein in a liquid such as water, a buffer, or the like, aIyophilized powder, an immunogenic composition comprising the protein and one or more adjuvants or immunogenicity enhancers such as are known in the art, or a pharmaceutical composition.

[0060] The isolated prestin protein of the invention may be made by a variety of techniques. For example, the protein may be expressed in an in vitro expression mixture using an isolated polynucleotide of the invention. The isolated polynucleotide of the invention may also be operably linked with a constitutive or other promoter, and the prestin protein is then over-expressed in a human or non-human cell, and subsequently purified therefrom. Alternately, the prestin protein may be purified using, for example, standard chromatographic techniques from a naturally occurring source of prestin protein (e.g. mammalian cochlear outer hair cells).

[0061] The isolated prestin protein can have an amino acid sequence completely homologous with SEQ ID NO: 1 or SEQ ID NO: 2, or it can comprise one or more conservative amino acid substitutions relative to either of these two sequences). For example, the protein can have an amino acid sequence which incorporates the differences between any two of the gerbil, murine, and human prestin amino acid sequences described herein. Furthermore, it is within the level of skill of the ordinary worker to determine the remainder of the sequence of the human pres gene (e.g. by constructing an oligonucleotide primer that is complementary to the end of BAC clone RG107G13 corresponding to pres, isolating a genomic fragment that hybridizes with the primer, and determining the sequence of the genomic fragment beyond that provided in BAC clone RG107G13). Thus, the present invention includes isolated human prestin as well.

[0062] Certain amino acids of prestin may be substituted for other amino acids without appreciably affecting the biological activity of the protein. Preferably, the amino acid sequence of the isolated prestin protein is substantially homologous with SEQ ID NO: 1 or the sequence of human prestin. The hydropathic index of naturally occurring prestin amino acid residues may be compared with those of potential substitute amino acid residues. The significance of amino acid hydropathic index similarity between naturally occurring and potential substitute amino acid residues, as it relates to retention of biologic function of a protein is generally understood in the art. It is accepted that the relative hydropathic character of the amino acid contributes to the secondary structure of the resultant protein, which in turn defines the interaction of the protein with other molecules, for example, enzymes, substrates, receptors, DNA, antibodies, antigens, and the like.

[0063] Each naturally occurring amino acid residue has been assigned a hydropathic index on the basis of their hydrophobicity and charge characteristics, as described (Kyte et al., 1982, J. Mol. Biol. 157:105). These hydropathic index values are: isoleucine (+4.5); valine (+4.2); leucine (+3.8); phenylalanine (+2.8); cysteine/cystine (+2.5); methionine (+1.9); alanine (+1.8); glycine (−0.4); threonine (−0.7); serine (−0.8); tryptophan (−0.9); tyrosine (−1.3); proline (−1.6); histidine (−3.2); glutamate (−3.5);glutamine (−3.5); aspartate (−3.5); asparagine (−3.5); lysine (−3.9); and arginine (−4.5). Amino acid residues may be substituted in place of other amino acid residues which having a similar hydropathic index without significantly affecting biological activity of the protein. Preferably, the substitute amino acid residue has a hydropathic index which differs from the hydropathic index of the naturally occurring amino acid residue by less than 2.0, preferably by less than 1.0, and more preferably by less than 0.5. For example, if the hydropathic index of a naturally occurring amino acid residue is 1.8, then a substitute amino acid residue should have a hydropathic index in the range from 3.8 to −0.2, preferably in the range from 2.8 to 0.8, and more preferably in the range from 2.3 to 1.3.

[0064] An alternate method may be used to predict amino acid residues which may be substituted in place of naturally occurring prestin amino acid residues in regions of prestin which are predicted to interact with other molecules, such as regions predicted to interact with the plasma membrane of cells. This method has been described in the art (Hoop et al., 1981, Proc. Natl. Acad. Sci. USA 78:3824), and involves assigning the following hydrophilicity values to amino acid residues: arginine (+3.0); lysine (+3.0); aspartate (+3.0); glutamate (+3.0); serine (+0.3); asparagine (+0.2); glutamine (+0.2); glycine (0); proline (0.0); threonine (−0.4); alanine (−0.5); histidine (−0.5); cysteine (−1.0); methionine (−1.3); valine (−1.5); leucine (−1.8); isoleucine (−1.8); tyrosine (−2.3); phenylalanine (−2.5); tryptophan (−3.4). Amino acid residues may be substituted in place of other amino acid residues having a similar hydrophilicity value without significantly affecting biological activity of the protein. Preferably, the substitute amino acid residue has a hydrophilicity value which differs from the hydrophilicity value of the naturally occurring amino acid residue by less than 2.0, preferably by less than 1.0, and more preferably by less than 0.5. For example, if the hydrophilicity value of a naturally occurring amino acid residue is 1.8, then a substitute amino acid residue should have a hydrophilicity value in the range from 3.8 to −0.2, preferably in the range from 2.8 to 0.8, and more preferably in the range from 2.3 to 1.3.

[0065] As outlined above, amino acid substitutions may be based on the relative similarity of the amino acid side-chain substituents, for example, their hydrophobicity, hydrophilicity, charge, size, and the like. For example, conservative amino acid substitutions may include substitutions within the following groups:

[0066] glycine, alanine;

[0067] valine, isoleucine, leucine;

[0068] aspartic acid, glutamic acid;

[0069] asparagine, glutamine;

[0070] scrine, threonine;

[0071] lysine, arginine;

[0072] phenylalanine, tyrosine.

[0073] Modifications (which do not normally alter primary sequence) include in vivo, or in vitro chemical derivatization of polypeptides, e.g., acetylation, or carboxylation. Also included are modifications of glycosylation, e.g., those made by modifying the glycosylation patterns of a polypeptide during its synthesis and processing or in further processing steps; e.g., by exposing the polypeptide to enzymes which affect glycosylation, e.g., mammalian glycosylating or deglycosylating enzymes. Also embraced are sequences which have phosphorylated amino acid residues, e.g., phosphotyrosine, phosphoserine, or phosphothreonine.

[0074] Isolated prestin protein, or a fragment thereof, may be used to generate polyclonal or monoclonal antibodies using known methods. As is well known, administration of prestin protein to an animal can induce a soluble immune response against the protein or fragment in the animal. Preferably, the protein or fragment is mixed with an adjuvant or other immune system enhancer. Such adjuvants include, but are not limited to, mineral gels such as aluminum hydroxide, surface active substances such as lysolecithin, pluronic polyols, and polyanions, other peptides, and oil emulsions. Antibodies which bind specifically with the prestin protein or fragment may be identified and isolated using well known methods (see, e.g. Harlow et al., 1988, Antibodies: A Laboratory Manual, Cold Spring Harbor, N.Y.). Likewise, immortal hybridomas may be generated using known methods to provide a supply of such antibodies.

[0075] The amino acid and nucleotide sequences of prestin and pres, respectively, which are provided herein can be used to diagnose a disorder associated with aberrant expression of pres. Aberrant expression of pres includes, for example, expression of prestin protein having an amino acid sequence that differs from the normal (i.e. wild type) sequence of prestin, over- or under-expression of pres relative to normal expression levels, expression of pres in tissues in which it is not normally expressed, and non-expression of pres in tissues in which it normally is expressed. By way of examples, disorders which are associated with aberrant expression of pres include various forms of deafness, other hearing impairment, and other hearing disorders, including disorders linked with the autosomal recessive locus designated DFN B14, such as a congenital, sensorineural, autosomal recessive form of non-syndromic deafness associated with this locus.

[0076] The amino acid and nucleotide sequences of prestin and pres, respectively, which are provided herein can also be used to treat a disorder associated with aberrant expression of pres. For example, wild type prestin protein or wild type pres can be provided to a cell which expresses less than a normal amount of the wild type protein (e.g. one which expresses a non-functional form of prestin or one which expresses no prestin). Alternatively, an antisense oligonucleotide which binds specifically with at least one strand of pres can be provided to a cell which expresses more than a normal or desirable amount of wild type or altered prestin protein, in order to inhibit or prevent such expression.

[0077] The ability of prestin to alter the surface area of a lipid bilayer, as described herein, can be used to affect the properties of either a naturally occurring lipid bilayer or a synthetic lipid bilayer. By way of example, providing prestin (i.e. in the form of the protein or in the form of a gene vector which will express the protein) to a cell renders the surface area of the plasma membrane of the cell susceptible to modulation by prestin. In the presence of an increased membrane potential (i.e. a membrane potential having a more negative value), a lipid bilayer comprising prestin is expanded relative to the surface area of the bilayer in the presence of a lower (i.e. less negative; more positive) membrane potential. If the lipid bilayer encloses a fixed volume (or a volume which cannot change as quickly as the surface area changes), then the tension within the bilayer is altered as the membrane potential changes. Thus, in the presence of a low membrane potential, the surface area of a lipid bilayer comprising prestin tends to decrease, so the surface tension of the bilayer increases if the bilayer surrounds a fixed volume, yielding a stiffer structure. Upon increasing membrane potential, the surface area of the bilayer increases, so the surface tension of a bilayer surrounding a fixed volume decreases yielding a more pliant structure.

[0078] The ability of prestin to modulate the surface area of a lipid bilayer can be used to modulate the volume of structure which is enclosed by a lipid bilayer if fluid can pass across the bilayer upon expansion or contraction of the bilayer mediated by prestin. Thus, for example, the volume (i.e. and diameter) of a ‘leaky’ (i.e. porous) bilammelar lipid membrane vesicle which comprises prestin can be modulated by changing the potential across the membrane. Similarly, the stiffness or shape of a structure which comprises a lipid bilayer surrounding a fluid can be modulated if the bilayer comprises prestin and if the rate at which the volume of the structure can change is less than the rate at which prestin can change the surface area of the bilayer (i.e. taking into account the geometric relationship between volume and surface area). Thus, a structure which comprises a lipid membrane comprising prestin enclosing a fixed (or relatively fixed) volume of fluid can be used as a force generator by interposing the structure between two surfaces upon which force can be exerted, restraining the ability of the structure to expand in a direction at least partially parallel to (i.e. absolutely parallel to or oblique with respect to) at least one surface, and modulating the membrane potential of the lipid membrane. Upon increasing the membrane potential (i.e., the electrical aspect), the structure expands in a direction normal to at least one surface, and outward force (relative to the structure) is exerted upon the surfaces, thereby urging the surfaces apart (i.e., the mechanical aspect). Upon decreasing the membrane potential, the structure contracts in a direction normal to at least one surface, and inward force (relative to the structure) is exerted upon the surfaces, thereby urging the surfaces together. Because structures comprising a lipid bilayer can be made on a microscopic (or even sub-microscopic) scale, these force generators can be exceedingly small, and are suitable for incorporation into very small (e.g. microscopic or nanometer-scale) apparatus.

[0079] It is also contemplated by the invention that by applying a mechanical force to prestin, an electrical impulse is created in response to the mechanical force. While the electrical impulse generated may be small, this aspect of the invention has use in electrical circuitry, and more specifically, in nanocircuitry. Thus, for example, prestin has the ability to modulate the electrical characteristics associated with the functions of the cochlea and, more generally, electrical functions associated with hearing.

[0080] Definitions

[0081] As used herein, each of the following terms has the meaning associated with it in this section.

[0082] The articles “a” and “an” are used herein to refer to one or to more than one (i.e. to at least one) of the grammatical object of the article. By way of example, “an element” means one element or more than one element.

[0083] “Antisense” refers particularly to the nucleic acid sequence of the non-coding strand of a double stranded DNA molecule encoding a protein, or to a sequence which is substantially homologous to the non-coding strand. As defined herein, an antisense sequence is complementary to the sequence of a double stranded DNA molecule encoding a protein. It is not necessary that the antisense sequence be complementary solely to the coding portion of the coding strand of the DNA molecule. The antisense sequence may be complementary to regulatory sequences specified on the coding strand of a DNA molecule encoding a protein, which regulatory sequences control expression of the coding sequences.

[0084] “Complementary” refers to the broad concept of sequence complementarity between regions of two nucleic acid strands or between two regions of the same nucleic acid strand. It is known that an adenine residue of a first nucleic acid region is capable of forming specific hydrogen bonds (“base pairing”) with a residue of a second nucleic acid region which is anti-parallel to the first region if the residue is thymine or uracil. Similarly, it is known that a cytosine residue of a first nucleic acid strand is capable of base pairing with a residue of a second nucleic acid strand which is anti-parallel to the first strand if the residue is guanine. A first region of a nucleic acid is complementary to a second region of the same or a different nucleic acid if, when the two regions are arranged in an anti-parallel fashion, at least one nucleotide residue of the first region is capable of base pairing with a residue of the second region. Preferably, the first region comprises a first portion and the second region comprises a second portion, whereby, when the first and second portions are arranged in an anti-parallel fashion, at least about 50%, and preferably at least about 75%, at least about 90%, or at least about 95% of the nucleotide residues of the first portion are capable of base pairing with nucleotide residues in the second portion. More preferably, all nucleotide residues of the first portion are capable of base pairing with nucleotide residues in the second portion.

[0085] “Homologous” as used herein, refers to nucleotide sequence similarity between two regions of the same nucleic acid strand or between regions of two different nucleic acid strands. When a nucleotide residue position in both regions is occupied by the same nucleotide residue, then the regions are homologous at that position. A first region is homologous to a second region if at least one nucleotide residue position of each region is occupied by the same residue. Homology between two regions is expressed in terms of the proportion of nucleotide residue positions of the two regions that are occupied by the same nucleotide residue. By way of example, a region having the nucleotide sequence 5′-ATTGCC-3′ and a region having the nucleotide sequence 5′-TATGGC-3′ share 50% homology. Preferably, the first region comprises a first portion and the second region comprises a second portion, whereby, at least about 50%, and preferably at least about 75%, at least about 90%, or at least about 95% of the nucleotide residue positions of each of the portions are occupied by the same nucleotide residue. More preferably, all nucleotide residue positions of each of the portions are occupied by the same nucleotide residue.

[0086] An “isolated” polynucleotide or protein refers to a molecule which has been separated from sequences which flank it in a naturally occurring state, e.g., a DNA fragment which has been removed from the sequences which are normally adjacent to the fragment, e.g., the sequences adjacent to the fragment in a genome in which it naturally occurs. The term also applies to molecules which have been substantially purified from other components which naturally accompany the nucleic acid, e.g., RNA or DNA or proteins, which naturally accompany it in the cell.

[0087] As used herein, the term “promoter/regulatory sequence” means a nucleic acid sequence which is required for expression of a gene product operably linked to the promoter/regulatory sequence. In some instances, this sequence may be the core promoter sequence and in other instances, this sequence may also include an enhancer sequence and other regulatory elements which are required for expression of the gene product. The promoter/regulatory sequence may, for example, be one which expresses the gene product in a tissue specific manner.

[0088] By describing two polynucleotides as “operably linked” is meant that a single-stranded or double-stranded nucleic acid moiety comprises the two polynucleotides arranged within the nucleic acid moiety in such a manner that at least one of the two polynucleotides is able to exert a physiological effect by which it is characterized upon the other. By way of example, a promoter operably linked with the coding region of a gene is able to promote transcription of the coding region.

[0089] A first oligonucleotide anneals with a second oligonucleotide “with high stringency” if the two oligonucleotides anneal under high stringency hybridization conditions.

[0090] By “high stringency hybridization conditions” is meant those hybridizing conditions that (1) employ low ionic strength and high temperature for washing, for example, but not limited to 0.015 molar NaCl, 1.5 millimolar sodium citrate, and 0.1% (w/v) sodium dodecyl sulfate (SDS) at 50° C.; (2) employ during hybridization a denaturing agent such as formamide, for example, but not limited to 50% (v/v) formamide, 0.1% (w/v) bovine serum albumin, 0.1% (w/v) Ficoll, 0.1% (w/v) polyvinylpyrrolidone, and 50 millimolar sodium phosphate buffer at pH 6.5 with 750 millimolar NaCI, 75 millimolar sodium citrate at 42° C.; or (3) employ 50% (v/v) formamide, 5×SSC (0.75 molar NaCl, 75 millimolar sodium pyrophosphate, 5×Denhardt's solution, sonicated salmon sperm DNA (50 micrograms per milliliter), 0.1% (w/v) SDS, and 10% (w/v) dextran sulfate at 42° C, with washes at 42° C. in 0.2×SSC and 0.1% (w/v) SDS. Under stringent hybridization conditions, only highly complementary nucleic acids hybridize. Preferably, such conditions prevent hybridization of nucleic acids having 1 or 2 mismatches out of 20 contiguous nucleotides.

[0091] The term “substantially pure” describes a compound, e.g., a protein, polynucleotide, or polypeptide which has been separated from components which naturally accompany it. Typically, a compound is substantially pure when at least 10%, more preferably at least 20%, more preferably at least 50%, more preferably at least 60%, more preferably at least 75%, more preferably at least 90%, and most preferably at least 99% of the total material (by volume, by wet or dry weight, or by mole percent or mole fraction) in a sample is the compound of interest. Purity can be measured by any appropriate method, e.g., in the case of polypeptides by column chromatography, gel electrophoresis or HPLC analysis. A compound, e.g., a protein, is also substantially purified when it is essentially free of naturally associated components or when it is separated from the native contaminants which accompany it in its natural state.

[0092] By the term “specifically binds,” as used herein, is meant a protein (e.g., an antibody) which recognizes and binds a prestin protein but does not substantially recognize or bind other molecules in a sample.

[0093] By the term “lipid bilayer”, as used herein, is meant a membrane formed by phospholipids in a bimolecular layer. This term should be construed to include naturally-occurring, as well as artificially prepared membranes.

[0094] The term “modulation” describes regulation of some quantity or measure of a product or process. For example, a protein is said to be modulated when expression is either increased or decreased.

[0095] The invention is now described with reference to the following Examples. These Examples are provided for the purpose of illustration only and the invention is not limited to these Examples, but rather encompasses all variations which are evident as a result of the teaching provided herein.

EXAMPLES Example 1

[0096] Prestin is the Motor Protein of Cochlear Outer Hair Cells

[0097] Tissue Preparation and Pres cDNA Isolation by Subtractive PCR Hybridization

[0098] Outer hair cells and inner hair cells are distinct sensory receptor cells in the mammalian organ of Corti. They both have hair bundles at the cell apex, though their bundle lengths, numbers and configuration are quite different. They both are rich in mitochondria in order to maintain their active physiologic function. It is likely that a vast array of housekeeping genes as well as genes that code for metabolism, the transducer apparatus and a variety of common ion channels are duplicated in IHC and OHC. These and other similarities between OHC and IHC make IHC an ideal “driver” in order to “subtract-away” common hair cell genes, allowing isolation of OHC specific genes. The use of inner and outer hair cells as sources of cell-type specific mRNA should reduce the number of candidate genes obtained after the subtraction-hybridization process and thus enhance the likelihood of successful isolation of OHC specific genes.

[0099] A unique and abundant OHC-specific cDNA from a gene, designated Prestin (Pres), has been identified herein via OHC minus IHC subtractive PCR hybridization and differential screening. The protein prestin is novel, but some of its regions exhibit moderate homology to pendrin and sulfate/anion transport proteins. Voltage-induced shape change can be elicited in human kidney (TSA201) cells that express prestin. The OHC's mechanical response to voltage change is accompanied by a “gating current,” manifested as nonlinear capacitance. This nonlinear capacitance was also demonstrated in transfected TSA201 cells.

[0100] The materials and methods used in the experiments presented herein are now described.

[0101] Mature gerbils were euthanized and the organ of Corti and associated basilar membrane were isolated by dissection as described in He et al.(1997, J. Neurosci., 15:3634-3643). The tissue was placed in calcium-free S-MEM medium, followed by brief trypsin treatment (1 milligram per milliliter) and trituration (20 minutes at 37 degrees Celsius). OHCs and IHCs were isolated in a low-calcium solution. Single OHCs and IHCs were identified and separated based on the presence of particular stereocilia configuration, depicted in FIG. 12. Using a glass pipette, the cells were separately isolated based on their morphological appearance and were collected in lithium chloride buffer. Messenger RNA was isolated from tissue using 20 microliters of oligo-dT magnetic beads (Dynal, Oslo, Norway). cDNA pools were created with Superscript II RNAase H reverse transcriptase (Gibco BRL, Gaithersburg, Md.) followed by amplification using a 5′-cap and oligo dT-dependent PCR technique according to manufacturer's specifications (SMART PCR™, Clontech, Palo Alto, Calif.). These cDNA pools were used for PCR subtractive hybridization, qualitative PCR, and virtual Northern (cDNA) dot-blot hybridization experiments.

[0102] The PCR subtractive hybridization procedures, control reactions, and subcloning were according to the manufacturer's instructions (PCR Select cDNA Subtraction Kit, Clontech). Clones were subjected to a differential screening procedure using a PCR-Select Differential Screening Kit (Clontech). PCR amplified cDNA inserts from these clones were denatured and vacuum filtered onto four identical nylon membranes. Each cDNA sample was separately hybridized with one of the following probes: forward subtracted (OHC-IHC) cDNA; reverse subtracted (IHC-OHC) cDNA; un-subtracted OHC cDNA; and un-subtracted IHC cDNA. These cDNA pools were random primed labeled with [³²P]-dCTP and hybridized to the blots. Positively hybridizing clones were scored for differential hybridization with forward (OHC-IHC) and reverse (IHC-OHC) subtracted probes. This differential expression was confirmed by correlation with simultaneous differential hybridization with the original un-subtracted OHC and IHC cDNA pools. Sequencing was performed using dRhodamine terminator cycle sequencing ready reaction kit (ABI Prism, Foster City, Calif.) and an automated DNA sequencer (Model 377, Perkin Elmer, Norwalk, Conn.). DNA and amino acid sequences were compared and analyzed using sequence analysis software of GCG and TMHMM (1998, Sonnhammer, et al., Proc. 6^(th) Intern. Conf. On Intelligent Systems for Mol. Biol., 175-182) and Tmpred (1993, Hoffman, et al., Biol. Chem., 347:166).

[0103] Virtual Northern (cDNA) Dot-Blot Hybridization

[0104] 0.5 Micrograms of SMART™ cDNA from gerbil thyroid, IHC, OHC, and 0, 6, 12, 16, and 20 day old organs of Corti were denatured and vacuum filtered onto membranes. A 1067 base pair NcoI restriction fragment of Pres cDNA was radioactively labeled with [³²P]-dATP and used as a probe (Strip-EZ Kit™ and UltraHyb™ buffer, Ambion, Austin Tex.).

[0105] PCR

[0106] PCR reactions used templates of 200 nanograms of SMART™ cDNA from gerbil thyroid, newborn and adult organs of Corti, isolated IHC, and organ of Corti from various post-natal ages (0 to 20 days after birth). Pres-specific primers (sense: 5′-TACCTCACGGAGCCGCTGGT-3′ (SEQ ID NO: 7), and antisense: 5′-GCAGTAATCAGTCCGTAGTCC-3′ (SEQ ID NO: 8)) were used to amplify an 863-base pair fragment from the cDNA. Cyclophilin primers (sense: 5′-TGGCACAGGAGGAAAGAGCATC-3′ (SEQ ID NO: 9), and antisense: 5′-AAAGGGCTTCTCCACCTCGATC-3′ (SEQ ID NO: 10)) that amplify a 301-base pair DNA fragment were used as an internal control. Cycle parameters were 3 minutes at 94 degrees Celsius followed by 25-30 cycles of 94 degrees Celsius for 45 seconds, 56 degrees Celsius for 45 seconds, and 72 degrees Celsius for 1 minute, with a final extension at 72 degrees Celsius for 10 minutes.

[0107] Transient Transfection

[0108] TSA201 cells, clones of human embryonic kidney 293 cells that express the simian virus 40 (SV40) large T-antigen in a stable manner, were cultured in DMEM with 5% fetal calf serum, 100 units of penicillin per millilter, and 100 micrograms of streptomycin per milliliters. Cells were plated for 24 hours before calcium phosphate transfection. The transfection reaction mixture contained:

[0109] a) control plasmid, pcDNA3.1; b) 2 micrograms of Pres cDNA plasmid; c) 2 micrograms of Pres cDNA plasmid plus 0.2 micrograms of green fluorescent protein (GFP) plasmid as transfection marker; or d) 2 micrograms of pendrin cDNA plasmid plus 0.2 micrograms GFP plasmid.

[0110] After 24 hours the transfected cells were used for electrophysiological and physical measurements. Large, rounded, non-clustered TSA201 cells exhibiting considerable granulation were selected for electrophysiological and motility experiments.

[0111] Capacitance Measurements

[0112] Whole-cell voltage-clamp recordings were made with an Axopatch™ 200B amplifier (Axon Instruments, Foster City, Calif.) Recording pipettes had open tip resistances of 2-3 megaohms and were filled with internal solution containing 140 millimolar CsCl, 2 millimolar MgCl₂, 10 millimolar EGTA, and 10 millimolar HEPES at pH 7.2. The external solution contained: 120 millimolar NaCl, 20 millimolar TEA-Cl, 2 millimolar CoCl₂, 2 millimolar MgCl₂, 10 millimolar HEPES, and 5 millimolar glucose at pH 7.2. Osmolarity was adjusted to 300 milliosmolar per liter with glucose. Capacitive currents were filtered at 5 kilohertz and digitized at 50 kilohertz using pClamp 7.0 software (Axon Instruments).

[0113] Voltage-dependent capacitance was measured using two methods. First, a standard P/4 linear subtraction procedure was employed to detect the presence of nonlinear charge movement. After nonlinear transient current was detected, a stair-step voltage protocol was used to obtain the parameters of charge movement. For each voltage step, the measured membrane capacitance (C_(m)) was plotted as a function of membrane voltage (V_(m)) and fitted with the derivative of a Boltzmann function: $\begin{matrix} {C_{m} = {\frac{Q_{\max \quad}\alpha}{{{Exp}\quad\left\lbrack {\alpha \left( {V_{m} - V_{1/2}} \right)} \right\rbrack}\left( {1 + {\exp\left\lbrack {- {\alpha\left( {V_{m} - V_{1/2}} \right\rbrack}} \right)}^{2}} \right.} + C_{lin}}} & (1) \end{matrix}$

[0114] where Q_(max) is maximum charge transfer, V_(1/2) is the voltage at which the maximum charge is equally distributed across the membrane, C_(lin) is linear capacitance, and α=ze/kT is the slope factor of the voltage dependence of charge transfer where k is Boltzmann's constant, T is absolute temperature, z is valence, and e is electron charge. From the stair-step analysis we have obtained the membrane resistance: R_(m)=130.45±20.14 megaohms.

[0115] Motility Measurements

[0116] TSA201 cells were drawn into a microchamber with gentle suction (FIG. 6A). The microchamber was mounted on a three-dimensional micromanipulator attached to the stage of a Zeiss inverted microscope. The most distal part of the excluded segment of the cell was imaged onto a photodiode with a rectangular slit interposed into the light path. A change of photocurrent signified cell extension or contraction. The signal was current-to-voltage transformed, amplified, A/D converted, and averaged. The command voltage, delivered between the electrolyte solutions (L15, Gibco BRL) surrounding and filling the microchamber, produces different voltage drops on the included and excluded cell membrane segments, determined by the electrical voltage-divider effect of these membranes. During motility measurements, the location of the cell within the slit was monitored via a video camera placed behind the slit. The appearance of the whole cell in the microchamber was also continuously displayed with the aid of a second video camera. This permitted an independent verification of a lack of movement of the microchamber itself.

[0117] The results of these experiments are now described.

[0118] Cloning of Pres and the Properties of Prestin

[0119] The molecular approach to identify the OHC sensor-motor protein faced two initial challenges: first, isolation of cDNA from limited amounts of biological material, and second, recognition of the candidate motor protein cDNA among the isolated unknown genes. Isolation of sufficient number of OHCs is a fairly routine task.

[0120] Obtaining comparable numbers of IHCs requires some modification of techniques. mRNA was isolated from approximately 1000 OHCs and 1000 IHCs and reverse transcribed followed by 5′-mRNA cap and oligo dT-dependent PCR amplification to obtain OHC and IHC cDNA pools.

[0121] Recognition of the cDNAs that encoded the candidate motor protein was based on the following assumptions: (1) the protein is expressed in OHC and not in the non-motile IHC, (2) ontogenic expression should relate to the known development of electromechanical responses, (3) the protein should be relatively abundant in OHC, (4) the protein should be a transmembrane protein, and (5) electromechanical responses should be demonstrable when expressed in a heterologous system. It was reasonable to expect that gene expression related to mechano-electric transduction and genomic, metabolic, and structural functions would be shared by these two types of hair cells. Therefore suppression subtractive hybridization PCR procedure was used to amplify and enrich the OHC cDNA pool for uniquely expressed gene products. This procedure uses two rounds of cDNA hybridization to subtract out common OHC cDNAs using a vast excess of IHC cDNA. The unique fragments are amplified by PCR, RsaI-digested, and cloned to create a library of candidate clones. This technique is useful because it simultaneously enriches for differentially expressed cDNA fragments and suppresses non-target DNA amplification.

[0122] Approximately 1300 fragment clones were screened using four cDNA pools (OHC-IHC, IHC-OHC, OHC unsubtracted and IHC unsubtracted) to identify differentially expressing clones (FIG. 1). Once false positive clones were excluded, 487 clones were identified as differentially expressing genes and of these, 108 clones were sequenced. These 108 sequences contained 50 unique cDNA fragments. Eighteen of the clones contained sequences which were highly similar to known proteins including Type I collagen pro-alpha 2, serine kinase, oncomodulin, ribonucleotide reductase, ATP synthase, etc., while 32 were believed to be unique in that there were no obvious homologous sequences to them in the genetic database searched. Eleven of the 32 apparently unique clones contained DNA having open reading frames. These were examined in greater detail by dot-blot hybridization using radioactively labeled clone cDNA against immobilized OHC and IHC cDNA pools. Pres was one of the eleven candidate clones identified. Pres fragments in the PCR subtracted library were abundant (>10% of 487 differentially expressed clones) and demonstrated consistent differential hybridization with OHC and IHC derived probes (FIG. 16).

[0123] Using one of these Pres cDNA RsaI fragments as a probe, three cDNA clones were subsequently isolated from a gamma-gt11 gerbil adult cochlea library. The largest of these clones was 4.1 kilobases in length having an open reading frame of 2232 base pairs, encoding a 744 amino acid protein (FIG. 2). The sequence around the putative translation start site contains a consensus Kozak sequence and an in-frame stop codon is present 12 bases upstream of this predicted start site. There is a short 223 base pair untranslated 5′ end and a large 1654 base pair, 3′ untranslated region. A computer search of the Pres sequence revealed that about one-third of the human PRES gene has been fortuitously sequenced as part of the human chromosome 7 effort (BAC clone RG107G13, bases 99,895 to >113,558). The amino acid homology between human and gerbil prestin, deduced from the genomic sequence of the first 6 exons, is 98% (FIG. 2).

[0124] Analysis of the prestin sequence revealed that its highest homology was to members of a family of anion/sulfate transport proteins including pendrin and DRA. The pendrin homology (40%) is of particular interest because this chloride-iodide transport protein is known to be a cause of the genetically inherited deafness observed in Pendred's syndrome. This homology, although modest overall, is similar to the homology among other members of the sulfate/anion transport family. Because gerbil cDNA was used and only rat, mouse, and human pendrin sequences were known at the time, it was necessary to demonstrate that prestin was not the gerbil homolog of pendrin.

[0125] It has been shown by others that mouse pendrin is expressed in the endolymphatic duct and sac, the utricle and saccule, and within the cochlea only in the external sulcus, but not in the organ of Corti. Confirmation that prestin was not a gerbil homolog of pendrin was achieved by cloning an 824 base pair fragment of gerbil pendrin cDNA, and demonstrating that the sequence was distinct from prestin. The gerbil pendrin amino acid sequence derived from the above cDNA fragment was 88% homologous to the amino acid sequence of human pendrin, but only 38% homologous to the amino acid sequence of gerbil prestin.

[0126] The protein prestin (744 amino acids; 81.4 kiloDaltons) is hydrophobic, containing approximately 50% non-polar residues; 27.8% of the protein is composed of the amino acids valine, leucine and isoleucine. Computer modeling of the amino acid sequence produces ambiguous results using multiple modeling programs. Specifically, the models TMHMM and TMPred report ambiguous results as to the number and location of transmembrane regions and are unable to predict the topology of the amino and carboxy termini in relation to the membrane. By comparison, when pendrin is subjected to the same modeling programs, 11 transmembrane regions, and an intracellular amino terminus are unambiguously predicted. The consistent ambiguity of the modeling programs with regard to prestin is potentially significant, and suggests that the mechanism by which prestin produces electromechanical action is by altering the protein/membrane interface as a result of voltage induced changes in its structure.

[0127] Two distinctive charged regions are located in the carboxy terminal region of prestin. A positive charge cluster of residues is located at 557-580; adjacent to the positive cluster, a negative charge cluster is at residues 596 to 613 (FIG. 2). Prestin's overall predicted hydropathy profile is similar to pendrin, DRA, and other members of the sulfate/anion transport family. The homology to pendrin is highest in the 50 amino acid region (97-146) that encompasses the sulfate transport motif (109-130), but does not have long regions of amino acid identity elsewhere. Instead, there is a pattern of moderate homology using both amino acid identity and similarity throughout the protein with multiple, discrete 8-12 residue segments of amino acid identity. The charged cluster regions of prestin are conserved in their net charges, but are otherwise not remarkably homologous. The proteins differ most in the region between the two charge clusters and at the termini. Although prestin exhibits high homology in the sulfate transport region, a highly conserved domain, found in homologs in organisms as distant as yeast, C. elegans, and plants, does not conform to the sulfate transporter signature as currently defined. Specifically, both human and gerbil prestin differ from the consensus sequence at three positions (FIG. 3). Consequently, while prestin appears related to sulfate transporters, these differences in the conserved region suggest that the protein may have distinct properties.

[0128] The tissue-specific and developmental expression pattern of Pres in the gerbil was also determined. Northern blot analysis using a Pres probe did not detect expression of prestin in liver, lung, brain, spleen, ovary, kidney, muscle, and heart (total RNA 20 micrograms). Virtual Northern dot-blot analysis using cDNA prepared from IHC, OHC, mature and newborn organs of Corti, and thyroid revealed prestin expression only in mature OHC and 20 day old organ of Corti (FIG. 4A). Similar results were obtained using Pres-specific primers and a qualitative PCR assay (FIG. 4B). Both virtual Northern and PCR exhibited progressively increasing Pres expression in isolated organ of Corti from birth up to 20 days after birth (FIGS. 4C and 4D), by which time electromotility is fully developed in the altricial gerbil. In OHCs, the motors are usually congruent with abundant approximately 10 nanometer membrane particles. The density of these particles in gerbil OHCs increases with development which density then decelerates toward adult values 16-18 days after birth. Thus the ontogenic expression of Pres is similar to that of membrane particles, electromotility, and the onset of high sensitivity hearing.

[0129] Functional Tests of Prestin

[0130] In order to investigate the function of the prestin cDNA, the functional properties of prestin in eukaryotic cells were examined. To accomplish this, Pres was subcloned into the eukaryotic expression vector pcDNA3.1. A carboxy-terminal epitope-tagged (V5) version (pcDNA6/V5-HisA vector) of the expression vector was created to facilitate detection of expression of the full-length protein in transfected cells. The expression of the V5 version was examined by indirect immunofluorescence to assure its presence in transfected cells. The epitope-modified prestin was found to be located in the cell membrane, with a punctate distribution in permeabilized cells. In addition, Western blot analysis using an anti-V5 antibody against transfected cell extracts demonstrated production of the appropriate sized prestin protein.

[0131] To test the sensor-motor function of prestin, voltage-dependent charge movement was measured in TSA201 cells after transient transfection of unmodified, native Pres cDNA. A second plasmid (pEGFP-N2) containing GFP cDNA was used as an independent marker for successful transfection of the cells. Transfection efficiency was 30-40% as judged from the fluorescence of GFP in transfected cells. Consistent with this, 36.8% of cells transfected with Pres alone displayed transient capacitive currents under voltage clamp using a standard subtraction protocol after blocking ionic currents (FIG. 5A). In experiments conducted on cells co-transfected with prestin and GFP cDNA, transient capacitive currents were obtained from 91.8% of the GFP positive cells. In contrast, untransfected cells or cells transfected solely with the control plasmid exhibited no measurable nonlinear capacitance. The capacitive currents were directed towards the outside as the membrane potential was depolarized and toward the inside as it was hyperpolarized. Charges transferred at command onset and offset were approximately equal. The decay of transient currents was rapid (100-200 microseconds) and could be well-fitted with a single exponential. The voltage protocol used to estimate membrane capacitance and charge transfer across the membrane was an ascending stair-step voltage waveform (FIG. 5B). The membrane capacitance was fitted to the derivative of a first-order Boltzmann equation (FIG. 5C). In a group of seven cells, these curve-fits yielded values of Q_(max)=1.76±0.20 pC, V_(1/2)=−57.30±2.98 mV, 1/a˜=kT/ze=28.00±2.13 mV, and C_(lin)=20.50±2.65 pF, respectively (mean ±SEM). The valence can be calculated from a, z=0.91. The average charge density, a possible measure of transiently transfected motor protein density in TSA201 cells, was 5360 square micrometers. The numerical values that characterize the charge movement (V_(1/2), z) are quite similar to those obtained for OHCs. The maximum charge and charge density are less in the transfected cells, even though the linear capacitance is about the same as that of an average OHC.

[0132] In OHCs, nonlinear capacitive current and electromotility can be reversibly blocked by sodium salicylate. As further evidence that transient currents stem from the transfected motor protein, salicylate was locally applied to cells that had been shown to present charge movement. Sodium salicylate (10 millimolar) reduced the transient currents to 15.5±2.9% of control (FIG. 5D). Of these, 3 cells showed recovery after 2-5 minutes of washing in normal extracellular solution without sodium salicylate (to 88.4±8.8% of control).

[0133] Finally, the existence of nonlinear capacitance was tested in cells that were transfected with both GFP and human pendrin cDNA. None of the GFP-positive cells demonstrated nonlinear capacitance. This result is significant because of the similarity of pendrin and prestin, demonstrating the specificity of the candidate motor protein. It also indicates that the electrophysiological results are not simply the consequence of the introduction of an anion transport protein.

[0134] In TSA201 cells the organized cytoskeletal network is probably missing, thereby making the conversion of mechanical molecular events to gross cellular deformation more difficult. Consequently, even if the motor protein is expressed, gross cellular deformation is expected to be very small. Furthermore, OHCs are efficient producers of axial motility because of their cylindrical shape. Fast mechanical effects occur at constant cell volume and are generally assumed to be the result of a change in cell surface area, due to the aggregate conformational shape changes of large numbers of motor proteins. A spherical cell cannot change its surface area while its volume remains constant, whereas a cylindrical cell can. In order to test that the generally spherical TSA201 cells may produce measurable motility, the cells were distorted to alter their shape by drawing them into a suction pipette (microchamber), thereby producing a dumbbell or hourglass shape (FIG. 6A). Electromotility in about 22% of cells tested was demonstrated. Two of the best responses are shown in FIG. 6B, in contrast to a trace from a non-transfected, non-responsive cell. The usual electrical driving signal was a brief 200 Hertz sinusoid. Sodium salicylate produces a reversible decrease in the electromotile response (FIG. 6C), just as it does in OHCs. In order to examine motility at higher frequencies, comparison between responses at 200 and 1000 Hertz are shown in FIGS. 6D and 6E. When corrected for the characteristics of the recording system, the two responses are essentially identical (FIG. 6E), in accord with OHC data obtained in the past.

[0135] The protein prestin has been shown to convey to a heterologous system novel mechanical responsiveness, almost indistinguishable from that measured in OHCs A portion of the human pres gene has been sequenced and mapped. The location of the motor protein in relation to the other members of its family can be predicted and any relationship to genetic loci known to be related to hearing disorders or deafness can be ascertained. The bacterial artificial chromosome clone (RG107G13) which contains a portion of the pres gene at its 3′ end, has a single known other gene, RELN, which is about 50 kilobases centromeric to the pres gene fragment. This location is approximately 3.7 megabases centromeric to the location of the pendrin (PDS) and DRA genes. Thus, it appears likely that pres is located in an as yet unsequenced portion of 7q31, centromeric to PDS and DRA, and 50 kilobases telomeric to the RELN gene.

[0136] There are at present two autosomal nonsyndromic recessive deafness loci mapped to 7q31 in addition to the PDS gene: DFNB14 and DFN3 17. DFNB14 is the most likely candidate to be pres, since it maps centromeric to the PDS gene locus, while DFNB 17 maps to the telomeric side of PDS and DRA. The proof that DFNB 14 is itself distinct from PDS is derived from the fact that, in the kindred analyzed, there were no useful polymorphic markers in a genomic region of 15 centimorgans that contains both the RELN gene and PDS. In this kindred, the PDS exons were sequenced and appeared to be normal, indicating that the causative mutation was distinct from that seen in Pendred's syndrome. The clinical phenotype in this kindred of a congenital, sensorineural, autosomal recessive form of non-syndromic deafness, is consistent with prestin's functional role.

[0137] These results support earlier work on OHCs, demonstrating that neither the subsurface cortical lattice nor the subsurface cisterns are essential for electromotility. It is unlikely that either of these organelles would be present in TSA201 cells, either in their native or transfected form. Demonstration of nonlinear capacitance and motility simplifies the concept of electromechanical changes in OHCs and obviates the need for exotic schemes. Presumed conformational changes of prestin, resulting in a change of cell surface area, produce dimensional changes in the cell. This is the basic electromotile response. It is contemplated that stiffness change may accompany these shape changes in TSA201 cells as they do in OHCs, thus the expression of prestin plays a role in the full electromechanical process.

[0138] While the reliance of the mammalian cochlea on local, OHC-based, amplification is widely accepted, there is no universal agreement about the amplifying mechanism. One view is that, powered by the cell's receptor potential, OHC electromotility provides mechanical feedback and thereby amplification. This view places the motor process in the cell's basolateral membrane and calls for a novel motor protein to drive somatic shape changes. An alternative concept is that amplification arises as a byproduct of the cell's forward transducer process and thus resides in the stereocilia. Whichever mechanism dominates, the existence of electromechanical action in OHCs is indisputable. The novel pres gene herein identified is the gene that codes for a specialized motor protein that produces this electromechanical action when expressed in cells that, in their native form, do not exhibit this phenomenon.

[0139] Isolated OHCs are capable of producing an average maximum axial isometric (stall) force of approximately 6 nanoNewtons (2000, He and Dallos, JARO, 1:64-81). From the number of molecules producing this force it can be estimated that the individual molecular stall force is on the order of 2.4 picoNewtons. In comparison, the stall force of kinesin is 5 to 6 picoNewtons. The potential of prestin to perform as a fast, voltage-driven actuator, individually or in assemblies, forming the basis of futuristic nanomachinery, is substantial.

Example 2

[0140] Isolation of a Novel Gene from Gerbil Outer Hair Cells

[0141] The materials and methods for the experimental procedures employed in this Example are now described. The methods are similar to those employed for Example 1.

[0142] Isolation of Outer Hair Cells (OHCs) and Inner Hair Cells (IHCs)

[0143] Mature gerbils were decapitated immediately following euthanasia. The organ of Corti and the associated basilar membrane were then treated with XX milligrams per milliliter of trypsin for 20 minutes at 37 degrees Celsius. OHCs and IHCs were obtained by gentle trituration of the trypsinized organ of Corti and the basilar membrane. The preparation was mounted on an inverted microscope as described in He, et al (2000, Hearing Res., 145:156-160).

[0144] Solitary OHCs and IHCs were identified by appearance and by the presence of a particular stereocilia configuration, shown in FIG. 12. OHCs and IHCs were then separately isolated by a small glass pipette (30-50 micrometers in tip diameter) mounted on a three dimensional stage micromanipulator. Approximately 1,000 IHCs and 1,000 OHCs were collected from 7 animals.

[0145] PCR Amplification

[0146] Messenger RNAs were isolated from both OHCs and IHCs using 40 microliters of oligo-dT magnetic beads in Lithium Chloride buffer (Dynal). OHC and IHC cDNA pools were created by reverse transcription using 200 units of Superscript II RNAase H reverse transcriptase at 42 degrees Celsius for one hour, followed by amplification with a 5′-Cap and oligo dT-dependent PCR technique according to manufacturer's instructions (Clontech).

[0147] PCR-Select cDNA Subtraction

[0148] In the subtraction experiment, OHC is the tester cDNA, and IHC is the driver cDNA. The OHC cDNA pool generated from PCR amplification was divided into two groups and then ligated to two different adapters (adapter 1 and 2). The OHC cDNAs were then subjected to two rounds of subtractive hybridization with excess driver cDNA, i.e., the IHC cDNA. After subtraction hybridization, the new hybrids carry different adapters (adapter 1 & 2), allowing them to be preferentially amplified. The hybrids with OHC-specific expressed genes underwent two rounds of selective PCR amplification. The PCR amplification, hybridization and control reaction were according to manufacturer's instructions (Clontech). As shown in FIG. 14, the distribution pattern of OHC cDNA subtracted with IHC is quite different from that of the unsubtracted OHC cDNA pool.

[0149] Construction of OHC Subtracted cDNA Plasmid Library

[0150] The final subtracted OHC cDNA pool was restriction digested with NotI and EagI and cloned into pGEM5Z(−), previously cut with NotI. The plasmid was then transformed into E. coli, produced an OHC subtracted cDNA plasmid library. 1320 Colonies were selected. A sample of these clones was used for T7/Sp6 PCR reaction to confirm the presence and the size of the inserts, as shown in FIG. 15. The PCR amplified cDNA was vacuum-filtered onto four identical nylon membranes (BioRad, Richmond, Va.) for hybridization. Forward-subtracted (OHC-IHC) and reverse-subtracted (IHC-OHC) cDNA, as well as tester (unsubtracted OHC) and driver (unsubtracted IHC) cDNA were radioactively labeled with ³²P-dCTP using a random primer labeling method. The cDNA was hybridized with 5×10⁶ counts per minute per milliliter of each individual probe overnight. After a final washing with 0.2×SSC/0.05% SDS, nylon membranes were exposed to autoradiographic film for 8 hours. Results are shown in FIG. 16. Positively hybridizing clones were scored for differential hybridization with forward (OHC-IHC; FIG. 16A) and reverse (IHC-OHC; FIG. 16B) subtracted probes. This differential hybridization was confirmed in most cases by confirming hybridization with tester (OHC; FIG. 16C) and driver (IHC; FIG. 16D) cDNA. In some cases, strongly differential hybridizing clones seen in the forward and reverse pair of blots were also selected for DNA sequencing despite a lack of signal from the tester and driver hybridization blots. 103 Clones were analyzed and selected from the OHC subtracted plasmid library. Of those, 18 clones were known genes, while 32 clones were unknown. Eleven of the unknown clones had evident open reading frames and 21 clones had no apparent coding sequence. Results for known genes are shown in Table 1. TABLE 1 KNOWN GENES NUMBER OF CLONES Collagen alpha-2 (I) 8 Mitochondria cytochrome c oxidase II 3 Acidic Protein Rich in Leucine (APRIL) 2 Mitochondrial tRNA 2 Oncomodulin 2 Adenine nucleotide translocase-2 (Ant2) 1 Acid sphiagomyleinase (ASM)-like 1 phosphodiesterase 3a ATP synthase 1 Collagen alpha-1 (I) 1 Glycerol 3 phosphate acyltransferase 1 Inward rectifier K-channel 1 Mitochondrial DNA control region 1 Mitochondrial 12S RNA 1 Osteonectin (SPARC: secreted protein 1 acidic rich in cysteine) Prolylcarboxypeptidase 1 Receptor tyrosine kinase 1 Ribonucleotide reductase 1 Serine kinase (SRPK2) 1

[0151] Virtual Northern Dot Blot Experiments

[0152] mRNAs were isolated using oligo-dT magnetic beads (Dynal) from thyroid, adult cochlea, newborn cochlea, IHC, OHC, and cultured organ of Corti treated with and without T3. cDNA pools from these tissues were created using the 5′-Cap PCR strategy as described above (Clontech). 0.5 Micrograms of each sample cDNA was mixed with 0.4 molar NaOH and 10 millimolar EDTA and then boiled at 100 degrees Celsius for 10 minutes. The cDNA samples were then vacuum filtered onto nylon membranes (BioRad). The membranes were neutralized with 0.5. molar Tris-HCl before hybridization. Unknown-gene fragments were radioactively labeled with ³²P-DATP according to Random Primed stripAble DNA probe Synthesis & Removal Kit™ (Ambion). Results for three genes are shown in FIG. 18.

[0153] Gamma-gt11 Gerbil Cochlea Library Screening

[0154] The library screening was performed using standard experimental procedure as described in, for example, Sambrook, et al., 1989 (Molecular Cloning: A Laboratory Manual, 2^(nd) Ed., Cold Spring Harbor Laboratory Press, New York).

Example 3

[0155] Prestin is a Cytoplasmic Protein

[0156] N-tagged and C-tagged prestin constructs were created in the same general manner as above and subsequently transiently transfected into TSA201 cells. Immunofluorescence with FITC-labeled secondary antibodies against prestin was used to determine where in the cells the prestin protein is expressed. It has been concluded that prestin is expressed in the cytoplasm of the TSA201 cells.

[0157] Generation of C-tagged and N-tagged Prestin Constructs

[0158] The C-terminal end of prestin was amplified using an oligonucleotide (5′-GCCCTGAATTCCTCGGGTGTGG-3′; SEQ ID NO: 13) which was complementary to the C-terminus of prestin, together with an upstream oligonucleotide primer (5 ′-GGACTACGGACTGATTACTGC-3′; SEQ ID NO: 14). The first primer was modified to create an EcoRI restriction site for ligation into an expression vector. PCR was performed with these primers, resulting in an amplified C-terminal fragment of prestin. The PCR product was cloned into the expression vector pcDNA6/V5-HisA (Invitrogen, Carlsbad, Calif.) to create a full-length C-terminus tagged with a V5 epitope located downstream and in-frame with prestin. C-tagged pendrin was also generated by this method.

[0159] The N-terminal end of prestin was amplified using an oligonucleotide complementary to the N-terminus of prestin (5′-CTGCAGAATTCGGATCATGCCG-3′; SEQ ID NO: 15) and a second downstream oligonucleotide primer (5′-CAACGATGGCTATGGCAATGGC-3′; SEQ ID NO: 16) in a PCR reaction. As above, the first primer was modified to create an EcoRI restriction site for ligation into an expression vector. The amplified PCR product was cloned into the expression vector pcDNA3.1/HisB (Invitrogen) to produce a full-length N-tagged prestin protein with an Xpress epitope located upstream and in-frame with prestin.

[0160] Generation of Prestin-Specific Antibodies

[0161] A peptide consisting of the first twenty N-terminal amino acids (MDHAEENEIPVATQKYHVER; SEQ ID NO: 12) was synthesized commercially and used to immunize two rabbits (SynPep Corporation, Dublin, Calif.). Twenty milliliters of serum from the first bleed was affinity purified by SynPep using standard affinity purification techniques.

[0162] Immunofluorescence

[0163] TSA201 cells transfected with the various prestin constructs were fixed 1 percent paraformaldehyde in PBS for 10 minutes at room temperature, followed by two washes with PBS. Permeabilized cells were incubated for 1 hour at room temperature with 500 nanograms per milliliter anti-prestin in PBS containing 0.1 percent saponin and 2 milligrams per milliliter bovine serum albumin (BSA). The cells were washed and incubated with Cy3-or FITC-conjugated anti-rabbit (or anti-mouse) IgG secondary antibody (Sigma, St. Louis, Mo.) in blocking solution (PBS containing 10 percent goat serum and 2 milligrams per milliliter BSA) containing 0.1 percent saponin. The saponin was used to permeabilize the cell membrane, allowing antibody to bind to intracellular epitopes. The cells were incubated at room temperature for 30 minutes, followed by a 15 minute incubation with 1 microgram per milliliter propridium iodide (PI, Molecular Probes, ), a membrane-impermeant DNA-binding compound used to test plasma membrane integrity. The cells were washed with PBS and mounted using Fluoromount-G™ (Southern Biotechnology Associates, Birmingham, Ala.). Nonpermeabilized cells were similarly treated with the exception of adding saponin to the incubation solution. All cells were then immediately observed using a Nikon Eclipse E400 Microscope.

[0164] In vivo fluorescence experiments were also conducted. Adult Mongolian gerbils were euthanized and decapitated. Cochleae were dissected out and incubated with 4 percent paraformaldehyde in PBS for 1 hour at room temperature (1999, Mammano et al., J. Neurosci., 19(16):6918-6929). The cochleae were then washed 4 times with PBS, followed by a 1-2 hour incubation at room temperature with blocking solution (PBS containing 5 percent goat serum and 2 percent BSA). Blocking solution for permeabilized samples also contained 0.1 percent saponin. Samples were washed again 4 times with PBS and then the tectorial membrane was dissected out. The remaining cochlear sample was divided into three segments by cutting the modiolus. The segments were immunolabeled with antibody and stained with PI as described above. Samples were observed using a laser confocal microscope.

[0165] Immunofluorescence of Native Prestin

[0166] Specificity of anti-prestin antibody was tested using TSA201 cells transiently transfected with the C-tag (V5 epitope) prestin construct. The cells were incubated with both anti-prestin and anti-V5 antibodies as discussed above, followed by extensive washing. The cells were then incubated simultaneously with FITC-labeled anti-rabbit IgG and Cy3-labeled anti-mouse IgG. The anti-prestin antibody attached to the FITC-labeled anti-rabbit IgG, fluoresced as green and the anti-V5 antibody, conjugated with Cy3-anit-mouse IgG, stained red.

[0167] Nonlinear Capacitance Measurements

[0168] The method for measuring nonlinear capacitance is discussed above. Nonlinear capacitance in TSA201 cells was measured in order to determine whether the attached V5 or Xpress epitope tags interfered with the normal function of prestin (i.e., voltage-dependent charge movement).

[0169] The results of the experiments are now described.

[0170] Nonlinear capacitance measurements demonstrated that when TSA201 cells are transfected with N-tagged prestin/GFP or C-tagged prestin/GFP, a typical nonlinear capacitance curve is observed (FIG. 20). This suggests that the V5 and Xpress epitope tags do not interfere with the voltage-dependent charge movement function of prestin.

[0171] Indirect immunofluorescence with FITC-labeled secondary antibody revealed that the anti-Xpress antibody (FIG. 21A) and the anti-V5 antibody (FIG. 21B) expressed green fluorescence in the plasma membrane of about one-third of the cells. This roughly reflects calcium phosphate transfection efficiency (about 30 percent) for TSA201 cells. Propidium Iodide staining was observed in nuclei of all cells. Cells transfected with control vectors did not express green fluorescence.

[0172] Because very few nonpermeabilized cells expressed green fluorescence and propidium iodide staining, it is proposed that these cells lacked plasma membrane integrity (FIGS. 22C and 22D). All of these data suggest that the N and C termini of prestin are located in the cytoplasm of TSA201 cells expressing the synthetic epitope tagged versions of prestin.

[0173] Immunofluorescence studies of native prestin were also performed. FIG. 22 depicts green fluorescence of cells, indicating the presence of the native prestin epitope in the cells. These cells also stained red, confirming the presence of the V5 epitope. The Xpress epitope apparently does not interfere with the immunofluorescent reaction of anti-prestin and its eptiope. These data suggest that the anti-prestin antibody specifically binds with prestin. FIGS. 24A and 24B demonstrate that prestin expression was observed in OHCs, but not in IHCs or other basilar membrane and organ of Corti cells. Prestin is localized in the basolateral wall of OHC as shown in FIGS. 24C and 24D.

[0174] Immunofluorescence results for permeabilized versus nonpermeabilized organ of Corti samples are shown in FIG. 24. Permeabilized samples are shown in FIGS. 24A and 24B and nonpermeabilized samples are shown in FIGS. 24C and 24D. Some nonpermeabilized cells, as in FIG. 24C, exhibited weak fluorescent staining. These cells may have damaged plasma membranes. The results shown in FIG. 24 further confirm that the N-terminus of native prestin is located in the cytoplasm.

[0175] The results ultimately suggest that both the C- and N-termini are located within the cytoplasm of cells. Both termini are possible sites of interaction with OHC cytoplasmic proteins. The results also suggest that the positive and negative cluster regions near the C-terminus may play a unique role in protein function.

[0176] The disclosure of every patent, patent application, and publication cited herein is hereby incorporated herein by reference in its entirety. While this invention has been disclosed with reference to specific embodiments, it is apparent that other embodiments and variations of this invention can be devised by others skilled in the art without departing from the true spirit and scope of the invention. The appended claims include all such embodiments and equivalent variations.

1 16 1 744 PRT Meriones unguiculatus 1 Met Asp His Ala Glu Glu Asn Glu Ile Pro Val Ala Thr Gln Lys Tyr 1 5 10 15 His Val Glu Arg Pro Ile Phe Ser His Pro Val Leu Gln Glu Arg Leu 20 25 30 His Val Lys Asp Lys Val Ser Glu Ser Ile Gly Asp Lys Leu Lys Gln 35 40 45 Ala Phe Thr Cys Thr Pro Lys Lys Ile Arg Asn Ile Ile Tyr Met Phe 50 55 60 Leu Pro Ile Thr Lys Trp Leu Pro Ala Tyr Lys Phe Lys Glu Tyr Val 65 70 75 80 Leu Gly Asp Leu Val Ser Gly Ile Ser Thr Gly Val Leu Gln Leu Pro 85 90 95 Gln Gly Leu Ala Phe Ala Met Leu Ala Ala Val Pro Pro Val Phe Gly 100 105 110 Leu Tyr Ser Ser Phe Tyr Pro Val Ile Met Tyr Cys Phe Phe Gly Thr 115 120 125 Ser Arg His Ile Ser Ile Gly Pro Phe Ala Val Ile Ser Leu Met Ile 130 135 140 Gly Gly Val Ala Val Arg Leu Val Pro Asp Asp Ile Val Ile Pro Gly 145 150 155 160 Gly Val Asn Ala Thr Asn Gly Thr Glu Ala Arg Asp Ala Leu Arg Val 165 170 175 Lys Val Ala Met Ser Val Thr Leu Leu Ser Gly Ile Ile Gln Phe Cys 180 185 190 Leu Gly Val Cys Arg Phe Gly Phe Val Ala Ile Tyr Leu Thr Glu Pro 195 200 205 Leu Val Arg Gly Phe Thr Thr Ala Ala Ala Val His Val Phe Thr Ser 210 215 220 Met Leu Lys Tyr Leu Phe Gly Val Lys Thr Lys Arg Tyr Ser Gly Ile 225 230 235 240 Phe Ser Val Val Tyr Ser Thr Val Ala Val Leu Gln Asn Val Lys Asn 245 250 255 Leu Asn Val Cys Ser Leu Gly Val Gly Leu Met Val Phe Gly Leu Leu 260 265 270 Leu Gly Gly Lys Glu Phe Asn Glu Arg Phe Lys Glu Lys Leu Pro Ala 275 280 285 Pro Ile Pro Leu Glu Phe Phe Ala Val Val Met Gly Thr Gly Ile Ser 290 295 300 Ala Gly Phe Asn Leu His Glu Ser Tyr Ser Val Asp Val Val Gly Thr 305 310 315 320 Leu Pro Leu Gly Leu Leu Pro Pro Ala Asn Pro Asp Thr Ser Leu Phe 325 330 335 His Leu Val Tyr Val Asp Ala Ile Ala Ile Ala Ile Val Gly Phe Ser 340 345 350 Val Thr Ile Ser Met Ala Lys Thr Leu Ala Asn Lys His Gly Tyr Gln 355 360 365 Val Asp Gly Asn Gln Glu Leu Ile Ala Leu Gly Ile Cys Asn Ser Ile 370 375 380 Gly Ser Leu Phe Gln Thr Phe Ser Ile Ser Cys Ser Leu Ser Arg Ser 385 390 395 400 Leu Val Gln Glu Gly Thr Gly Gly Lys Thr Gln Leu Ala Gly Cys Leu 405 410 415 Ala Ser Leu Met Ile Leu Leu Val Ile Leu Ala Thr Gly Phe Leu Phe 420 425 430 Glu Ser Leu Pro Gln Ala Val Leu Ser Ala Ile Val Ile Val Asn Leu 435 440 445 Lys Gly Met Phe Met Gln Phe Ser Asp Leu Pro Phe Phe Trp Arg Thr 450 455 460 Ser Lys Ile Glu Leu Thr Ile Trp Leu Thr Thr Phe Val Ser Ser Leu 465 470 475 480 Phe Leu Gly Leu Asp Tyr Gly Leu Ile Thr Ala Val Ile Ile Ala Leu 485 490 495 Leu Thr Val Ile Tyr Arg Thr Gln Ser Pro Ser Tyr Lys Val Leu Gly 500 505 510 Gln Leu Pro Asp Thr Asp Val Tyr Ile Asp Ile Asp Ala Tyr Glu Glu 515 520 525 Val Lys Glu Ile Pro Gly Ile Lys Ile Phe Gln Ile Asn Ala Pro Ile 530 535 540 Tyr Tyr Ala Asn Ser Asp Leu Tyr Ser Asn Ala Leu Lys Arg Lys Thr 545 550 555 560 Gly Val Asn Pro Ala Leu Ile Met Gly Ala Arg Arg Lys Ala Met Arg 565 570 575 Lys Tyr Ala Lys Glu Val Gly Asn Ala Asn Ile Ala Asn Ala Ala Val 580 585 590 Val Lys Val Asp Gly Glu Val Asp Gly Glu Asn Ala Thr Lys Pro Glu 595 600 605 Glu Glu Asp Asp Glu Val Lys Tyr Pro Pro Ile Val Ile Lys Thr Thr 610 615 620 Phe Pro Glu Glu Leu Gln Arg Phe Met Pro Gln Thr Glu Asn Val His 625 630 635 640 Thr Ile Ile Leu Asp Phe Thr Gln Val Asn Phe Ile Asp Ser Val Gly 645 650 655 Val Lys Thr Leu Ala Val Met Val Lys Glu Tyr Gly Asp Val Gly Ile 660 665 670 Tyr Val Tyr Leu Ala Gly Cys Ser Pro Gln Val Val Asn Asp Leu Thr 675 680 685 Arg Asn Arg Phe Phe Glu Asn Pro Ala Leu Lys Glu Leu Leu Phe His 690 695 700 Ser Ile His Asp Ala Val Leu Gly Ser His Val Arg Glu Ala Met Ala 705 710 715 720 Glu Gln Glu Ala Ser Ala Pro Pro Pro Gln Asp Asp Met Glu Pro Asn 725 730 735 Ala Thr Pro Thr Thr Pro Glu Ala 740 2 4113 DNA Meriones unguiculatus 2 gcggccgcgt cgacggcagc ggcggctccg ccctgcgcag ccccggcagc gctggctggt 60 ggcgggggag ggcgaacagt cccttttcca gccctcagca gttgactgcc ctgtacctgg 120 agttcccagc cggctttcca tcccctgtac cttgtgctat acgttggatc tggtgcctgt 180 ccagaaatgc tcgtctcctg ctgttggtga ataactgcag accatggatc atgccgaaga 240 aaatgaaatc cctgtggcaa cccagaagta ccacgtggaa aggcctatct tcagtcatcc 300 cgtcctccag gagaggctgc atgtcaagga caaagtctca gagtccattg gggataagct 360 gaagcaggcg ttcacatgca ctcccaaaaa gataagaaac atcatttaca tgttcctgcc 420 catcactaag tggttgccag cttacaagtt caaggagtat gtgttgggtg acttggtttc 480 aggcataagc accggcgtgc ttcagcttcc ccaaggctta gccttcgcaa tgctcgcggc 540 tgttcctccg gtgttcggcc tgtactcttc attttatcct gttatcatgt actgtttctt 600 tgggacctcc agacacatat ctataggtcc tttcgccgtc attagtttga tgatcggtgg 660 tgtggctgtc cggctggtcc ccgatgacat cgtcatcccg ggaggagtga acgcaaccaa 720 cggcacggag gcccgagacg cgctgagagt gaaagtcgcc atgtctgtca ccctgctctc 780 aggaatcatt cagttttgcc taggtgtgtg caggtttgga tttgtggcca tatacctcac 840 ggagccgctg gtgcgagggt tcaccaccgc cgccgccgtg cacgtcttca catccatgtt 900 gaaatacctg tttggggtta agacaaagcg gtacagtggg atcttttcgg tggtatatag 960 tacagttgct gtgttgcaga atgttaaaaa cctcaacgtg tgttccctag gcgtcggcct 1020 gatggttttt ggtttgctgt tgggtggcaa ggagtttaat gagagattta aagagaaatt 1080 gccagcaccc attcctctag agttctttgc tgtggtgatg ggaactggca tttccgcggg 1140 gtttaacttg cacgagtcct acagtgtgga tgtcgttgga actcttcctc tggggctact 1200 ccctcctgcc aacccggaca ccagcctctt ccacctcgtg tatgtggatg ccattgccat 1260 agccatcgtt ggattttcag tgacaatttc catggccaaa accttggcga ataagcatgg 1320 ctaccaggtt gatggcaatc aggagctcat cgctttgggg atatgcaact ccatcggatc 1380 tctcttccag accttctcca tttcctgctc cttgtctcgc agccttgttc aggagggaac 1440 tggagggaaa acacagctcg caggttgctt ggcctcgctg atgattctgc tggtcatttt 1500 agccactgga ttcctctttg agtcattgcc ccaggctgtg ctctcggcca ttgtgatcgt 1560 gaacctgaaa gggatgttta tgcagttctc agatctgccc ttcttctgga gaaccagcaa 1620 aatagagctg accatctggc ttaccacctt tgtgtcctcc ctgttcctgg gcttggacta 1680 cggactgatt actgctgtga tcattgctct gctgactgtg atttacagaa cccagagtcc 1740 gagctacaag gtcctggggc agctccctga caccgatgta tacattgaca tagacgcata 1800 tgaggaggtg aaagaaattc ctggaataaa aatattccag ataaacgccc caatttacta 1860 tgcaaacagt gacttgtata gcaacgccct aaaaagaaag actggtgtga acccagcgct 1920 cataatggga gcaagaagga aggccatgag gaagtacgca aaggaagtcg gaaacgccaa 1980 cattgccaac gcagctgttg tcaaagtgga tggagaagta gatggagaaa atgctacgaa 2040 gcccgaagaa gaggatgatg aagtaaaata tcccccaata gtcatcaaaa caacatttcc 2100 tgaagagctg cagagattta tgccccagac agaaaatgtc cacactatca ttctagactt 2160 cacacaagtc aattttatcg actctgttgg agtaaaaacc ctggctgtga tggtgaagga 2220 atacggagat gttggtattt atgtgtactt agcaggatgc agcccacaag tcgtgaatga 2280 cctcacccgc aaccgtttct ttgaaaatcc tgccttaaaa gagcttctgt tccacagtat 2340 ccatgatgca gtcttgggca gccatgttcg agaggcaatg gctgagcaag aagcctcagc 2400 cccacctccc caggacgaca tggagcccaa tgccacaccc accacacccg aggcataaag 2460 ggcctgcctg ggcctgtgca cctcttgaat tctgaactta catgctttaa ataccaggcc 2520 ttaggttttc ttctacccaa cccccaaccc ccaaggaaaa tgttagtagt tatggcttga 2580 tttggagggt gaatgatgtg tagtgcgatg tatctcagac ttgtgttatt ttatctgaat 2640 aattcaaaga ttaagtggcc tttcgcactt atgtagtgat gtttgtatta tatcttaaag 2700 tcaaaaaaaa aaaaaaaaaa aaaaagtcga cgcggccgcg gtcgacgcgg gcgcgaattc 2760 gcggccgcgt cgactttttt tttttttttt tttttttttc ttgtcaacat tttaatgcaa 2820 acaatatagt gtttttgact ctaggcatct gtaacgaaac agtgctagaa tgggataagc 2880 atctgcagct tctgtggagt gaatgcaatt agaactactc tgcccctgac tgcagaagcc 2940 aggcattgtg gcccacacct gccaacctcc actgaggagg ctacggcagg acgatcacag 3000 tgagttccag gccagcctgg gctacagagg gaggctcaaa ccccaaaact aaacaaatta 3060 aaaacaaaac aaaaaccaag gggaaattct tgtcaagctc ctttgaaagc tgatgtttca 3120 aagcacagga tttgtcttct ctagtagaga tatatttcct aagggagtgg aaggagtaag 3180 gttcaggctt acctgtctgt gaaacaccac aagcagtctc atccagacca ctgcttcccc 3240 tgactccctt tgcacatgga ggacaaacac ttggagagga acttaggtga cctgcttgct 3300 gcaaaaatca actatcaaga aagatttgga gaaacgctag tctgagaaac gagattacaa 3360 gagcctgtgg atttcttccc tgcaacactg gggccaacct ttcatgtctg atcagaaata 3420 acgggcatag tgtttattgt aagcctgaac catgaagaca gagcactgag ataggaagcc 3480 catttgacag tggcaatttc aaattaacag cttagttatg atggaacaca aactgcaaag 3540 gccttcattt cctgtgtttg gatgaagtca cgatccaaca gtgggttaag agtgtggaag 3600 gtagaaggca gcagctgaac tgttgtgagt ggtccaagga ggcagagatg cttcaagcac 3660 tcctcgccac cctcagcttc tcttcaagga gccaagagga tgaggagctg gtgcacccag 3720 agggtctaac cggggcttgc agagtcctaa agacatctct ctgcaggcag aaattgcaca 3780 gcttaattct tctagactga acagcttcag atttatgcca gtggaaagca aacattgttt 3840 ctaagtcatt taattgtgtt actgtctctc aactttatca gatgttgctt gggtagagag 3900 gcctgtgtgc agttctgagg gcggctttat ggtgctccct ggctccttct aaatgcccac 3960 agcccagagt ccctaatgga gcactttcca gatgtaaaaa ctactaattc aaaaggttca 4020 aatggcattt gtctcaatcc aggacgcaca ctgaaggctg catcttcacc aaatcgacaa 4080 ccttgatcgc aggtgctagg tcgacgcggc cgc 4113 3 744 PRT Mus sp. 3 Met Asp His Ala Glu Glu Asn Glu Ile Pro Ala Glu Thr Gln Arg Tyr 1 5 10 15 Tyr Val Glu Arg Pro Ile Phe Ser His Pro Val Leu Gln Glu Arg Leu 20 25 30 His Val Lys Asp Lys Val Thr Glu Ser Ile Gly Asp Lys Leu Lys Gln 35 40 45 Ala Phe Thr Cys Thr Pro Lys Lys Ile Arg Asn Ile Ile Tyr Met Phe 50 55 60 Leu Pro Ile Thr Lys Trp Leu Pro Ala Tyr Lys Phe Lys Glu Tyr Val 65 70 75 80 Leu Gly Asp Leu Val Ser Gly Ile Ser Thr Gly Val Leu Gln Leu Pro 85 90 95 Gln Gly Leu Ala Phe Ala Met Leu Ala Ala Val Pro Pro Val Phe Gly 100 105 110 Leu Tyr Ser Ser Phe Tyr Pro Val Ile Met Tyr Cys Phe Phe Gly Thr 115 120 125 Ser Arg His Ile Ser Ile Gly Pro Phe Ala Val Ile Ser Leu Met Ile 130 135 140 Gly Gly Val Ala Val Arg Leu Val Pro Asp Asp Ile Val Ile Pro Gly 145 150 155 160 Gly Val Asn Ala Thr Asn Gly Thr Glu Ala Arg Asp Ala Leu Arg Val 165 170 175 Lys Val Ala Met Ser Val Thr Leu Leu Ser Gly Ile Ile Gln Phe Cys 180 185 190 Leu Gly Val Cys Arg Phe Gly Phe Val Ala Ile Tyr Leu Thr Glu Pro 195 200 205 Leu Val Arg Gly Phe Thr Thr Ala Ala Ala Val His Val Phe Thr Ser 210 215 220 Met Leu Lys Tyr Leu Phe Gly Val Lys Thr Lys Arg Tyr Ser Gly Ile 225 230 235 240 Phe Ser Val Val Tyr Ser Thr Val Ala Val Leu Gln Asn Val Lys Asn 245 250 255 Leu Asn Val Cys Ser Leu Gly Val Gly Leu Met Val Phe Gly Leu Leu 260 265 270 Leu Gly Gly Lys Glu Phe Asn Glu Arg Phe Lys Glu Lys Leu Pro Ala 275 280 285 Pro Ile Pro Leu Glu Phe Phe Ala Val Val Met Gly Thr Gly Ile Ser 290 295 300 Ala Gly Phe Asn Leu His Glu Ser Tyr Ser Val Asp Val Val Gly Thr 305 310 315 320 Leu Pro Leu Gly Leu Leu Pro Pro Ala Asn Pro Asp Thr Ser Leu Phe 325 330 335 His Leu Val Tyr Val Asp Ala Ile Ala Ile Ala Ile Val Gly Phe Ser 340 345 350 Val Thr Ile Ser Met Ala Lys Thr Leu Ala Asn Lys His Gly Tyr Gln 355 360 365 Val Asp Gly Asn Gln Glu Leu Ile Ala Leu Gly Ile Cys Asn Ser Ile 370 375 380 Gly Ser Leu Phe Gln Thr Phe Ser Ile Ser Cys Ser Leu Ser Arg Ser 385 390 395 400 Leu Val Gln Glu Gly Thr Gly Gly Lys Thr Gln Leu Ala Gly Cys Leu 405 410 415 Ala Ser Leu Met Ile Leu Leu Val Ile Leu Ala Thr Gly Phe Leu Phe 420 425 430 Glu Ser Leu Pro Gln Ala Val Leu Ser Ala Ile Val Ile Val Asn Leu 435 440 445 Lys Gly Met Phe Met Gln Phe Ser Asp Leu Pro Phe Phe Trp Arg Thr 450 455 460 Ser Lys Ile Glu Leu Thr Ile Trp Leu Thr Thr Phe Val Ser Ser Leu 465 470 475 480 Phe Leu Gly Leu Asp Tyr Gly Leu Ile Thr Ala Val Ile Ile Ala Leu 485 490 495 Leu Thr Val Ile Tyr Arg Thr Gln Ser Pro Ser Tyr Lys Val Leu Gly 500 505 510 Gln Leu Pro Asp Thr Asp Val Tyr Ile Asp Ile Asp Ala Tyr Glu Glu 515 520 525 Val Lys Glu Ile Pro Gly Ile Lys Ile Phe Gln Ile Asn Ala Pro Ile 530 535 540 Tyr Tyr Ala Asn Ser Asp Leu Tyr Ser Ser Ala Leu Lys Arg Lys Thr 545 550 555 560 Gly Val Asn Pro Ala Leu Ile Met Gly Ala Arg Arg Lys Ala Met Arg 565 570 575 Lys Tyr Ala Lys Glu Val Gly Asn Ala Asn Val Ala Asn Ala Thr Val 580 585 590 Val Lys Val Asp Ala Glu Val Asp Gly Glu Asn Ala Thr Lys Pro Glu 595 600 605 Glu Glu Asp Asp Glu Val Lys Phe Pro Pro Ile Val Ile Lys Thr Thr 610 615 620 Phe Pro Glu Glu Leu Gln Arg Phe Leu Pro Gln Gly Glu Asn Val His 625 630 635 640 Thr Val Ile Leu Asp Phe Thr Gln Val Asn Phe Val Asp Ser Val Gly 645 650 655 Val Lys Thr Leu Ala Gly Ile Val Lys Glu Tyr Gly Asp Val Gly Ile 660 665 670 Tyr Val Tyr Leu Ala Gly Cys Ser Pro Gln Val Val Asn Asp Leu Thr 675 680 685 Arg Asn Asn Phe Phe Glu Asn Pro Ala Leu Lys Glu Leu Leu Phe His 690 695 700 Ser Ile His Asp Ala Val Leu Gly Ser Gln Val Arg Glu Ala Met Ala 705 710 715 720 Glu Gln Glu Ala Thr Ala Ser Leu Pro Gln Glu Asp Met Glu Pro Asn 725 730 735 Ala Thr Pro Thr Thr Pro Glu Ala 740 4 2441 DNA Mus sp. 4 gcagtggcgg ctccgcccag cgcagccccg ggcagcgctg gtggccggga agggctcatc 60 gtcccttttc cagccctcgg cagtttactg cggccctgta cctggagctc tggctgggtg 120 gtcatctcct gcccttgtgc tgtacgttgg atctagtggc catccagaaa tgcttgtctc 180 ctgctgttgg tgaataactg cagaccatgg atcatgctga agaaaatgaa atccctgcag 240 agacccagag gtactacgtg gaaaggccca tcttcagtca tcctgtcctc caagagaggc 300 tgcacgtcaa ggacaaagtc acagagtcca ttggagataa gctgaagcag gcattcacgt 360 gtactcctaa aaaaataaga aacatcattt acatgttcct gcctatcact aagtggctgc 420 cagcatataa attcaaggag tatgtgttag gtgacttggt ctcgggcata agcactgggg 480 tactccagct tccccaaggc ttagccttcg ccatgctggc agccgtgcct ccggtgtttg 540 gcctgtactc atcgttttac cccgttatca tgtactgttt ctttggaacc tcaagacaca 600 tatctatagg tccttttgct gttattagct tgatgattgg aggtgtggcc gtccggttag 660 taccagatga tattgtcatc ccaggaggag taaatgcaac caacgggaca gaagccagag 720 atgcactaag agtgaaagtc gccatgtctg ttaccttact ttcaggaatc attcagtttt 780 gcctaggtgt ctgtaggttt ggatttgtgg ccatatacct cacggagcca ttggtgcgag 840 gctttaccac tgcggctgct gtccacgtgt tcacgtccat gttaaaatac ctgtttgggg 900 tcaaaacaaa gcggtacagt ggaatctttt cagtggtgta tagtacagtt gctgtgttgc 960 agaatgttaa aaacctcaac gtgtgttccc taggcgtcgg cctgatggtt tttggtttgc 1020 tgttgggtgg caaggaattt aatgagagat ttaaagagaa attgccagca cccattcctc 1080 tagagttctt tgctgtggtg atggggactg gcatttctgc aggatttaac ctacatgagt 1140 cctacagtgt ggatgtcgtt ggaacacttc ctctggggct acttcctccg gccaacccag 1200 acaccagcct gttccacctg gtgtatgtgg acgccattgc catcgccatc gttggatttt 1260 cagtgacgat ctccatggcc aaaaccttgg caaataagca tggctaccag gttgatggca 1320 atcaggagct cattgccttg gggatatgca actccattgg atctctcttc caaaccttct 1380 cgatttcctg ctccttgtct cgaagccttg ttcaggaagg aactggaggg aaaacacagc 1440 ttgcaggttg tttggcctcg ttgatgattc tgttggtcat attagccacc ggattcctct 1500 ttgagtcgtt accccaggct gtcctttccg ccattgtgat cgtcaacctg aaaggaatgt 1560 tcatgcagtt ctcagacctg cctttttttt ggagaaccag caaaatagag ctgaccatct 1620 ggctgaccac ctttgtgtcc tccctgttcc tcggcttgga ctacggactg attaccgccg 1680 tgatcattgc tctgctcaca gtgatttata gaacacagag tccaagctac aaagtcctgg 1740 ggcagctccc tgacacggat gtgtacattg acatagatgc atatgaggag gtgaaagaaa 1800 ttcctggaat aaaaatattc caaataaatg ccccaattta ctatgcaaat agcgacttgt 1860 atagcagcgc tttaaaaaga aagactggag taaacccagc actcattatg ggagcgagaa 1920 gaaaggccat gaggaagtac gccaaggaag ttggaaatgc caacgtggcc aatgctactg 1980 ttgtcaaagt ggatgcagaa gtagacggag aaaatgctac aaaacctgaa gaagaggatg 2040 atgaagtcaa atttccccca atagtcatca aaacaacatt tcctgaagag ctgcagagat 2100 ttttgcccca gggggaaaat gtccacactg tcattctaga ctttacgcag gtcaattttg 2160 tggattctgt tggagtgaaa actctggccg ggattgtgaa agaatatgga gatgttggaa 2220 tttatgtata tttagcagga tgcagcccac aagttgtgaa tgacctcacc cgcaacaact 2280 tttttgaaaa tcctgccttg aaagagcttc tgttccacag tatccacgat gcagtcctgg 2340 gcagccaagt tcgggaggca atggctgaac aagaagccac agcgtcactt ccccaggagg 2400 atatggagcc caatgccaca cccaccaccc ccgaggcata a 2441 5 295 PRT Homo sapiens 5 Met Asp His Ala Glu Glu Asn Glu Ile Leu Ala Ala Thr Gln Lys Tyr 1 5 10 15 His Val Glu Arg Pro Ile Phe Ser His Pro Val Leu Gln Glu Arg Leu 20 25 30 His Val Lys Asp Lys Val Ser Glu Ser Ile Gly Asp Lys Leu Lys Gln 35 40 45 Ala Phe Thr Cys Thr Pro Lys Lys Ile Arg Asn Ile Ile Tyr Met Phe 50 55 60 Leu Pro Ile Thr Lys Trp Leu Pro Ala Tyr Lys Phe Lys Glu Tyr Val 65 70 75 80 Leu Gly Asp Leu Val Ser Gly Ile Ser Thr Gly Val Leu Gln Leu Pro 85 90 95 Gln Gly Leu Ala Phe Ala Met Leu Ala Ala Val Pro Pro Val Phe Gly 100 105 110 Leu Tyr Ser Ser Phe Tyr Pro Val Ile Met Tyr Cys Phe Phe Gly Thr 115 120 125 Ser Arg His Ile Ser Ile Gly Pro Phe Ala Val Ile Ser Leu Met Ile 130 135 140 Gly Gly Val Ala Val Arg Leu Val Pro Asp Asp Ile Val Ile Pro Gly 145 150 155 160 Gly Val Asn Ala Thr Asn Gly Thr Glu Ala Arg Asp Ala Leu Arg Val 165 170 175 Lys Val Ala Met Ser Val Thr Leu Leu Ser Gly Ile Ile Gln Phe Cys 180 185 190 Leu Gly Val Cys Arg Phe Gly Phe Val Ala Ile Tyr Leu Thr Glu Pro 195 200 205 Leu Val Arg Gly Phe Thr Thr Ala Ala Ala Val His Val Phe Thr Ser 210 215 220 Met Leu Lys Tyr Leu Phe Gly Val Lys Thr Lys Arg Tyr Ser Gly Ile 225 230 235 240 Phe Ser Val Val Tyr Ser Thr Val Ala Val Leu Gln Asn Val Lys Asn 245 250 255 Leu Asn Val Cys Ser Leu Gly Val Gly Leu Met Val Phe Gly Leu Leu 260 265 270 Leu Gly Gly Lys Glu Phe Asn Glu Arg Phe Lys Glu Lys Leu Pro Ala 275 280 285 Pro Ile Pro Leu Glu Phe Phe 290 295 6 29485 DNA homo sapiens 6 aagataatgt taaaaattat ttcacaaacc ttgcatcctt agtgtattcc agcattacgg 60 aatgaaggtc accacaagaa gtggcttcac aacccaccac aatctaaaac aaacataaac 120 aatcaataca caggtaagat tagatgatac tgaattccat taattaaaat cccatccgtc 180 catttattac tctgataggt aatattcaga gaagctttta tagagcagcc tgctgggata 240 ccaagaatac attcttttgg attctgttaa agatgttcaa ttttgcatgg agataaaaat 300 aaaggtttta aaagttacat ttctatgtac taaattagta taataaaaaa ttaatcacaa 360 atctgggtaa gataaactgg ccaaaaagaa agtaacatta gtcaaattta tagacagaaa 420 ctgaaagtat cactgattca aaacaatttc attgatagcc taactttctt gattgttact 480 attaaatttt tagttggaat taaaatcagc aattttaatt acttaatatt cgttcttggg 540 gttttctgta tttccatatc aatgaaagct ttccatatta tatgcaatta aatgtttgaa 600 tcattaataa tacataaatg ctataaaaat ttggtgattc aaatttaagt cctaatcatc 660 tatttaatca tgtcctattt cagcactgat aactagggaa ggttagtgtt aaaaatttca 720 ggccatacag tcatgaataa aacaactcta aattcagaga gagaataaga agcataatga 780 tagtgggaat cataatacac aaatataatg ctgtggtgct tcaaaggaga tagtatttga 840 ttcagtggat tagaaaataa tcagatagat agggtacatg cgagctgccc ctgaagactg 900 ggaagagtgt gagaggtaga gataggaaaa agatatttag gtgaaagaaa gagtgtgagt 960 gaagacaaag tagggaatca tggtgggaca tcaagagcac agtatatagc atgttttggt 1020 ccaagtatat cgtatatgaa atattcagag atgaggttag aatgatcggt tgaatttggc 1080 agaccagaag ctgcagccta aggtgtttga ccttaatttg gtaagtgatg gagagtcatt 1140 aaaggtttct gtggaatgat gtgctgctta gagatatgct ttataaagat caatctgacc 1200 atgatgtcaa agacagatag gagtggagag agagagattg ggagtgaaaa gagtacttag 1260 tcaactgttg atttagttag ggccagaaag gaggtggtga tagtgcaaac agagaagatt 1320 ggatggatac caggaacact ggaaagtaga attcaaagga tgtagtcact gattagatat 1380 gaaaagtgaa aaatcaaagc ctagttgaac atttcaagct agttactagg tgattggtgg 1440 tgccatcgac agaaacagga aaatcagagg agttggtatg gtgagggaag atattaagtg 1500 caccgttaga cacattcagt tgaggtgcca atgtgcaaag gtgtagaaat gtgtaggggc 1560 tattaaaata ttgaattaat tgttagccag tcaaggttgg atgtgcagat ttgaaatttg 1620 ctcttcaaga tatgattctt gaagctagat gattggatac aattcctgat ggtgagaatg 1680 tctatggaga gagaagaaag ttgatacata ctgagaaatg ctgacattta gagggctgag 1740 gggagaaaag ccataagaag ataacagata tcaaagaggt agaaggagaa cgagcagaga 1800 acccagaagc ctaggggaaa gagaattcca caggttgaag agggcaagaa taacagtgtc 1860 aaatagtgta gagaggaaag agaaggtggg gaatgtgcaa aaactgttga tattgggtac 1920 ggtaagtctc tgctgacttt caagtatgta gttttagtga tactttacta aatttttgag 1980 gatagactct ctttttttcc taaagaaatt gccttggtta tagaaagaga gacccagtct 2040 cttcagtgca gttacttctg ttacagaagt aacaaaagag gaggctccaa tcaactcaat 2100 caaatataat acctttgatc tgggccacaa tgtgaacctg ggagagggaa aatcttcact 2160 cttaaggaac agggcttaga agtagaggaa gtgtaacact tcttcatatc actaagctaa 2220 gaatactcct gaaggagtgg tagcatttgg ggagcttgcc ttaccctcca gtccccaaag 2280 gagagtttaa catagagctg aggcgaaaag caaatacatt tttatttctg ctagtaagga 2340 tttttactat taactgtcat tgtagtacat caaaaaaggg tattagaata actgatgtct 2400 ttaaaatgac ctagtaatac aatacatttc tgtaatgact tttgtgtgtg tgtgtgtgtg 2460 tgtgtgtgtg ggatatggtc ttgttctgtt gccctagctg gagtgcagta gtgggatcat 2520 agctcactgt aacctccaac cactgggctc gagtgattct tgtgcctcag cttcctgagc 2580 agctaggact acaagtacat gccaccacgc ccagctaatt tttttttttt tttttttttg 2640 gtagagatag ggggtcttgc tatgtttccc aggatggtct tgaactcttg gcctcagaga 2700 tccttcctcc ttggcctccc aaagtgctgg gattacaggt gtttgcaata gagatacatc 2760 aattgatatt gctttgcctt tctctgagtg tctattaatt atttatgtct tcactttcat 2820 cctatatgaa tcaagtattc agtttaaaat atttgagagt cctccttaat tttttgagga 2880 tttaggaagt tccaacagga ctaatgtagt ataggcatat gaagtcagag acacaagaaa 2940 atagaaagat acactggaaa aaaaatagat ggagaaaaaa tggctcaatg cacataatag 3000 gcatggagta agataaagag gaaggggaga gacagcggaa gggaagggag agagagagaa 3060 ctgtgcaaca taaaaaggag atagtgttac agagtagaga tagaagtagg cagagtgccc 3120 tatttgagct ttctatttac aagggtaggg agactgaaat ccagattaca tatataagat 3180 agaatatatt cagttggtgt aaaagtaatt gcggtttttg ccattaaaag aattggcatt 3240 aaaagtaatt cctttttttt tttttttttt ttgagacaga atctcgttct gtcgcccaca 3300 gtgcagtggt atgatcttgc ctctcaggtt tcagcgatta ttatttctca gcctcccaag 3360 tagctgggat tacaggtgtg cactaccacg actggctttt ttattttatt tattttttta 3420 tagagacaag gttttgccgt gttggccagg ctagtctgga gctcctggcc tcttggcctc 3480 aagtgatcct cctgccccag cctcccaaag tggtgggatt ataggcatgg ttccactgca 3540 cccggcctgc aattactttt gcaccagcct aatagttaca tttcttgcta tgtcccaaca 3600 ttttcaggga ttttatctat cctcaagtaa tcatacttga ataaaggtct ttgcaaaaga 3660 tgacctcttt tattcataag ataaagtctt ttttaatgaa taatatcagt catttcctta 3720 tagttgtctg actaaccatt ctccctcgag gccccaaatg caatgctact ttctgtttta 3780 aagagccact tttccttact ttaaactgca tcatgtatcc tggctgtata atgagttctc 3840 gggaggagag agcattgtga gtcttgtcct tctttttatt tggccaatag aggtgaaagg 3900 atggattgcc acaaaatcct gctgtcctta cagcattagg gtaaaaactc cagttttctt 3960 catgggaagt gccttctgtt aaggaaaatt ggaagcaata tggcatatta ttctcttgag 4020 gaaaattgga agcaatatgg catattattc tcttgaactg accgatttat tgttgaattc 4080 cttaaatttt tatgctctac tagctttctg cttacacttt aggattgatt tttattttat 4140 ttaactggga taatgcataa atccaacgtg agaaatcaaa ctttgacaag actattaaat 4200 ggtagtataa tgattaccgt acttttaaaa tgtaattgct agtctaggta acctagcacc 4260 gaaaagttct tgatacactt tgtcagccag tgcattaagt atttctgtga cacattaatt 4320 actaaagaaa ctaaaattat tttcgggtat tgaaatttca aattatattt aaagccagac 4380 attgagcctt taacatgatt tattgaatgc tcagtggaca tttcaaaaag cagccaactt 4440 tgaagattta taaaccactg ggcaaaataa cagctaacat ttgttgagca ggagtatggg 4500 ctaggcactc ttataaatgc ttttcatgtg ctaatctatc tgaagacata agcagaaaaa 4560 tggctcacag gaaagaaaat tgttcaatgt cttgtttctt accatcatca aaagtgtcca 4620 ccaattggct gggattgatt tctgctccac caatcaaaat gttgtccagt gcccactgag 4680 cacgctccac cccagagacc acaattccat tgctgatcac aaaaggctgc caccagcgaa 4740 gtcgagttgt gttggtgagg gcatcttcag gaagaagtat gtagtcgtgt ctaacagaaa 4800 tgtatttctg gtaatccatc tcatggagca aagtccaggt aattcctata ataacaaata 4860 taccaacata gcaatatatc tagaatctcc tgcctcctca taaaccacca gtatacttca 4920 gatactgtga acttcccaaa gaaattttca gccaggaaat gacaactgat tttcctgact 4980 ttgatattag gtattcacta cttatactgt ttctgtatga ggctaatgat atgaggggaa 5040 ggatatttcg aaagagttgg ccaaaataaa aacactgaag taaaaataag ttatgttttg 5100 cttttaaaat ttagttctaa attcttattt ctcacaaata atgagataca cccatgtttt 5160 acatgtttct aggcaatagc tttcagtatt aaaatagtta ttgtaatttt atgcaattta 5220 attatttgga ctggtataaa gtttatctct tcttgcttga taagattgca ggtgggatgt 5280 ttaattactt aagaaaacat ccttcaaata ccttaaaata ctttagggtc atctgttaat 5340 cagctagtta ttaagaatga tatctatctg ctaaagcaga tttttctaaa gacaccatgg 5400 tattactggt ctggttttag ctacttcaga ataacaaaac agaattctat taaaatattc 5460 tatgacaaac tcacaaaatc agactttttt ttcacaattt tagaagattt ccatagatta 5520 tagcatttat tacatgctta tttacacata agctgttaaa aatgctttaa agttttaaaa 5580 atgatctttt acttggaaat catacaaaat gtatttctta attgtatcac tcaagcttca 5640 gtaaagcgta gaggttgttt tctttattca taaagtttgg actttatttt taatgtgatt 5700 tctctccttc cctttttgca taacacagaa gtcacttgta cggaacatgt aatacaaaca 5760 aaatctgtag ctttttcttt gtgagtttca caattcaaac tgtgaagtca gcaaagcttt 5820 gcagagactt ttctgagggt gttggatgga atttgggaat ctgctccaag gggtggtttt 5880 cacccctgac acatgcctcc atcggtagag tagtccaaca gcacgccttc cttccggcag 5940 atgggacgat ggcaagaggt catgttgttc tcactaccga tgcgccccca gtattgcagg 6000 aacctgaatg caagcacatt ttatccatca gaataattca ttagaacaaa tactctactc 6060 aagtcctgga taatttcttc catacaagtg ttccttgctt tgggaccaat ttgctatggt 6120 gcaatagaaa taactaacaa aaaattcact tactttgcac ctcgaagatc caaatcttgt 6180 gtaaccgctt gtctcacagt ggatccccca aaatagagtg cagtgtcctc ggcaagaatt 6240 ccacactcag tgcaagtact tccaccttct aaggacatcc ataagtcagg tttgatttct 6300 tcactgtcaa agcgttcctt caggaaagtc tggaaataaa ataagccaga tgtggttaaa 6360 aaaacaattt cagataacta tggaatattt aagaaaatac agagtgatgt cttggactta 6420 aaaaaaatag agctgatttc aaatgctttt caaagatgtt taaaaaaggc tatttccaca 6480 atcttttttc ctgtcgtata ttgaaaatca tttaaactgc tcaaataatg tttaataatt 6540 gaaatttaaa ataattgtaa agttgactat atcaattttt ttttttgaga cgaagtcttg 6600 ctctgtcact tgggctggag tacagtggca caatctcaac taactgcagc ctctgcctcc 6660 cgggttcaag caattctcat gcctctgcct cctgagtagc tgggattaca ggtgtgtgcc 6720 accacacctg gctatttttt gtatttttca tagagatggg gtttcaccat gttggctagg 6780 ctggtctcga atccctgacc tcaagtgatc tgcccacctc cgcctcccag agtgctggaa 6840 ttacaggtgt gagccaccat gcctggccat attatagtaa cacttctatt tgtaaaaagt 6900 tagttagtta tttaagcata tacccccaaa catgtatatt tgtttatata gtatataaaa 6960 gtattattgt aatgtattat attatgaaac atgccaaaag gaatttgaaa gcaataagat 7020 aaaatataaa catgcaatcc agcactttcc ccctgacatt ccccaatgga ttgtcctggt 7080 gtgtgtgccc tcactttgga gactgcttca ggcagccagg atccttcagc ctctagcaca 7140 gaatgaacct tgaaggtcta catggttagg cagggacact tgaaaccaaa tctctctata 7200 taagtcaaaa gaaagtaaac ctttgaaggc agtttgaaag atgtttcacc tgtttatcag 7260 gccaagttgc agggtgataa gtactcaaaa tctagaatac aatattttcc cctgagtctc 7320 cagtttatcc ttttaactaa gaatgattga caaccagaaa atctattttt cagagagtgt 7380 acaaagtata aaggttcttg gctacatttt tttgtaaaat ttgcttatct cctcatagtc 7440 aaggtcttaa tttccctatt cattctgtct acagtacttt cattttatcc ataatgcaga 7500 tttgtattag gtagagacac atttcttgtt taaaatgatg aaaagatatc ataaagccaa 7560 tttgttctag ttgcaatgca ataactgtat acagaaaaac ctatattttt tcatttaagg 7620 agagttctat cttactgtgt agttaaaatg atttaaacag tttctttttc tcaaacttag 7680 aagataatca attctatagt taaagacata cagtcaaatg tcagtctgcc ttagtctcac 7740 taatggatag caaatgaata cgttttataa ttgaaagctt gtaagaagac aagtgttaga 7800 agaaatgcat ggttaaccac gtaaactttc attagaagat tttaatcagg gtttataatt 7860 tatagatttg tacaatttct tatccaactg aggaatacta ataaaatttg agtgctcatg 7920 aaagaaatta gattttcaaa agtttattaa ttacctgtgg tatataaagc tttgtttttc 7980 atgtggtaac ctcatttgtt aataatgtac ttacatcttc agacacaaat gagcattgtt 8040 ccaattttat ttaaaaaatg ttcaattcca tagttgaagt attagaacaa acacaaatga 8100 cagaacaggt ttgatttaca ttgttgactc tcatatgttg gatttcaatc actaggaatt 8160 ttgctttttt tagcctagtc atttttctgt tattgtaatg acaaatgcac tatgtttatt 8220 cacagaaata gagtgcatat gtggcaactg tgttgggtaa ctgtatttgc tttgcatatt 8280 aaataatgat gtaacagcta aagctttcaa aagtgacctc tccattctta atacacaacc 8340 ccatttcagc agtcaacgaa tcagaacaca gaattttcta aacaaaaatt caggtactgt 8400 ttaggccttt ttgaaaattt ggtcttttgt gataatgtat attatttgct ttatttcata 8460 acaataataa caataatatc ttccttcaaa tagtgcatca attgaaaaag tgaagtaaaa 8520 aaggcttaat attgacttta aaaatagtct gcttaagaaa aaaaaaagaa acccagagta 8580 tttatcattt gtaatccata tagtctggct cattttatga actggataaa ctgtactaga 8640 acttgatcct aatattcttg tacttaggaa acataagaca tttttaaagt ttctattcaa 8700 aggattttct ttcctggggg acccaaagga cattgttata gattatgtct catacataag 8760 ttggttccta ggcatgaccc atgatgtgag taatgcgtct tgtccagggc tttaccctta 8820 ccttcagagt gtgggtcaag tagcagtttg gccctgagta tcccggatca cagatgcact 8880 gttcccttaa gcaatctcca tggcccctgc agttgtccaa gcatccaggg cccaggtaga 8940 aattatcgat tgcccactgc atgtctgagt acttctgata gaacctaaac cttaccggac 9000 tattgacaat gcaaaagcaa aggagtgaaa aacaaaagtt aactgtattt aggtccattg 9060 tcctgcatgt gtattcagta ctcaagagaa aaaacattta agatactctt actagatgaa 9120 ataggttaat aaaaaatgtt ttctgaccac tcttatcttt ctagtaatgg aactttcaag 9180 ctggttttat tgaaatttca gaatatctga gcacacttgc acaacaaaat taaatcagtg 9240 gaatctctgt gtcaagaaat aaatagaaat atttaaatac acaaatctgt aactttcata 9300 aatcaggttt cttctgaatt ggagttccgt ggtcatgatg caatttagat tcactaattg 9360 catttctgaa attgtacaga aggtgagtga cgcctttgac aagagccttg tcagcataca 9420 cacagccctc aggcggtcgg gaggcagcat tttctgaatt ccctgaagac aatcaatatt 9480 ctcagagtaa ctatgctaat tagaaaacaa ttttgaaagg gttatattaa aggacatttt 9540 ctttgagatt ttaatttcat ctttgttctt ctctgtcttc tgggggaaaa aacaagcctc 9600 ataattatcc ttatattaaa atatgccata ctattttggt ttaaagaatc caaagtacat 9660 gaaggaactt tctggggtga tataaatgtt ctgtatcttg ttttatgtgg tggttacatg 9720 ggttacacaa ctaaaaactc attgatctga acaattaaga tgtatgtatt ttactgaatg 9780 taaattatac ctcattatta caaaaagaga atgggaggag aaaatgagtc tgtgatagac 9840 atcatggtgg gtccccagca tccatttcac cccagataat ccatgaaata atcatttcct 9900 aactcaacta ttgagtggct aattggtacc agtgggatgc aaggtggcgc ttgttctggc 9960 tgtcttggaa caaaagcaac tatctttctt tctcactgga cgtaagtacg gaagcatcct 10020 gccccagttc tctggctgcc atctcatgtt caatagcaaa accagcctga gagagctgag 10080 tatgccgcca gtgccgtgga cagcagatat tctcttaaga ggataaggag gaacgctgtc 10140 cctgaagaca ccgttcaact tacaaatcaa ccagccctag agttcactta tctttggatt 10200 cgttcattat agatataaca aatttcgagc tggtttgaat tgggttttct gttccttgca 10260 gctgaaagca tcctgattta attccttagt atgttaattg aataagctct ttagatacat 10320 tccagaaaac cctgagtggt aataataata ataataatat ctatgggaca ctgggaactg 10380 tgcgtaagca ctttattcaa agactcttta tgtttcacaa gatttgttta gtcagactat 10440 ctgattaata cagtctaggt gcacctgtta ttttcttttg tgtatcttta cttttaaagt 10500 agaagagaaa tcttttggaa ttgccttaaa ttaatatatc cacagacttt gcagagcaag 10560 gtttaatcac ctctgctcat cactggtcca ggctaattac ctctcactgc aggatcagaa 10620 tacaatgctt tgataagaga aaaatggatc ccataagtca cagtggtaga aatagcatga 10680 tgagttagga tttgctcctg gctctgtcta tcatggattg ataaggcaat aatgtggaaa 10740 gtatatagtg cacagaggtc cacagtctac aaggttgaga aggtagggta caccttttca 10800 tctggctcca aggccatcac tattgctctg ttcccatttt aagatactga ggtttagaaa 10860 ataagagtct gcaaaagccc atattgccaa gtctgaggat tacaaattga ggtctgaagt 10920 tagctcatca tggaagttat gatgaaagta accaattaga gaacctttag agttagggag 10980 aaagaaagca ctttacccac aaatacacat aatttcaggc atgacaacag tgtacctaat 11040 ggtgtacctt ctggatgctt ggaaccaggc tttgttttag ttttctactt actttcccac 11100 taagctttca ggaagtgggt aggtgatcct tttccaccct ttagttggaa agaatacaga 11160 tggctgagaa acacttccag agcattttgg gtcagcaggc aagcactgag ggaccagata 11220 attccaactc acaccgaagt cagtagaata ctgcacatga atttgattct gggcaatttt 11280 ttcagacacc ttacatccaa ctgagatcta ataaacagaa aaacaagatc aaggtattaa 11340 aactatatga tatgattctt ctccaaggac ttggcagcaa aaaagctgct gatcacttga 11400 tatacactgt accacatcca tcctgtattt tcagattcat tatttgttct gctaatggac 11460 agagaaagtc accatgattg ccccaggtga caaattatag aaagtgccaa atatattgtg 11520 tagggggttt ggagagaaac tcagaccccg tgcttctgcc atgctggctg aatgccttgg 11580 aaggcctggg ctcactccta caaactgtta gttgtgctaa tggtctggca tttctatttg 11640 gcagaatact taaccaagaa gaatagctaa cagctttacc aattttacta ttttgttgta 11700 caatttatga ctctcaatac aacactttca acgacaagta agatgaaata ataactgaag 11760 gtagtttaaa caaggcacag cacccttcgt tgatggtgat agccatgatg tgacactgct 11820 gttaatacag tgggatttag gtagacagaa taaattggtt cacataaaat cttggcctaa 11880 atattagcca aaattgatgt tgacattaat gctaatcatg cctttgtttt ctataaattt 11940 ttttctccag aaacatccaa atgttcttgt aaaaaaaaaa aaaaaaaaaa aaaaactaga 12000 ggctgggtgc catggctcac gcctgtaatc ccagcacttt gggaggccga gacgggtgga 12060 tcacgaggtc aggagtttga gaccagcctg accaacatgg tgaaaccctg tctctactaa 12120 aaatacaaaa attagctggg catggtggcg tgcacctgta atcccagcta ctcaggagcc 12180 tgaggcagga gaatcgtctg aacccgggag gcagaggttg cagtgaacca agattacgcc 12240 actgcactct agcctgggca acagagcaag actccgtctc agaaaaaaag gtcttatttc 12300 acctaaattt ctaagttata gttagtatta atagagagat gggtaagagg aaaaaaagta 12360 gaaataacca ttatagcttt aattttctct tgttgaaaca aattgcttaa gtcataatga 12420 tttaactcgg agttataatc agtatcctac atttttattg ttgatatttt tatctatcag 12480 tatttcatcc tgagcaggaa cacatttact cttataaaag tttcagcttg agagacagct 12540 ggcaagatgg ctgaatagga acagctccag tctgcagctc ccagcaagat caatgcagaa 12600 ggtgggtgat ttcggcattt ccaactgagg aacccggttc atctcattgg gactggttgg 12660 acagtgggtg cagcccatgg agggtgagct gaagcagagt gtggcagaac cacaaggggt 12720 cgggggattt ccctttccta gccaagggaa gccgtgagca actgtgctgg gaggaacagt 12780 gcaatctggc ccagatactg cgcttttccc acagtctttg caactggcag accaggacat 12840 tcccttcggt gcctggctca gtgagtccca cccccacgga gcccagcaag gtaagattca 12900 ctggcttgaa attctcgctg ccaacacagc agtctgaggt cgaactggga tgctcgagct 12960 tggtttgggg aggggcgtct gccattactg aggcttgagt aggcggtttt cccttcactg 13020 tgtaaacaga gccacccaga agtttgaaat gggtggagcc cgcctcagct cagcaaggcc 13080 aactgccact ctagattcct cctctctggg cagggcatct ctgaaaaaaa ggcagcagcc 13140 ccagtcaggg acttatagat aaaacttcca tctccctggg atagagctcc tgggggaagg 13200 ggtgctgtgg gcacagcttc agcagactta aacgtccctg cttgacagct ctgaagagag 13260 cagcggttct ctcagcacag catttgagct ctgataaggg acaggctgcc tcctcaagtg 13320 aaaccctgac ccctgtgtat cctgattggg agacacctcc cagtaggggc cgacagacac 13380 ctcatacagg agagctccgg ctggcatctg gtgggtgccc ctctgggatg aagcttccag 13440 aggaaggaac aggcagcaat ctttgctgtt ctgtagcctc tgttggtgat acctaggcaa 13500 acagggtctg gagtggacct ccagcaaact gcaggagacc tgcagcagag gggcctgact 13560 gccagaagga aaactaacaa acagaaagga atagtatcaa taccaacaaa aaggaggtcc 13620 actcatagac cccatcctaa ggtcaccaac atcaaagacc aaaggtagat aaatccacga 13680 agatggggag aaaccagcgc aaaaaggctg aaaattccaa aagccagaaa attccaaaag 13740 ccagaatgcc tcttctcctc caaaggatca caactcctcg ccagcaaggg aacaaaacga 13800 gatggagaat gagtttggca aattgacaga agtaggcttc agaaggtggg taataacaaa 13860 ctcctccaag ctaaaggcgc atgttctaac ccaatgcaag gaagctataa gaaccttgaa 13920 aaaaggttag agggactgct aactagaata accagtttag agaagaatat aaatgacctg 13980 atggagctga aaaacacagc acgagaactt cgtgaagcat acacaagtat caatagccga 14040 atcgatcaag tggaggaaag aatatcagag aatgaagatc aaatcaatga aataaagtgg 14100 gaagacaaca ttagagaaaa aagagtgaaa agaaacaaag cctccaagaa atatgggact 14160 acgtgaaaag accaaatcta tgtttcatca gtgtatctga aagtgatggg gagaatggaa 14220 ccaagttgga aaacactctt caggatatta tccaggagaa cttccccaac ctagcaaggc 14280 aggccaacat tcaaattcag gaaatacaga gaacgccaca aagatacata atcgtcagat 14340 tcaccaaggt tgaaatgaag gaaaaaatgt taagggcagc aagagagaaa ggtcgggtta 14400 cccacaaagg gaagcccatc agactaacag cagatctccc tgcagaaacc ctacaagcca 14460 gaagagagtg gaagccaata ttcaacattc ttaaagaaaa gagttttcaa tccagaattt 14520 catatccagc caaactaagc ttcataagcg aaggataaat aaaatccttt acagacaagc 14580 aaatgctgag agatttttgt caccaccagg cctgccttac aggagctcct gaaggaagca 14640 ctaaacatgg aaaggaacaa ccagtaccag ccactgcaaa aacataccaa attgtaaaga 14700 ccattgatgc tttggataaa ctgcataact aatgggcaaa ataaccagct agcatcataa 14760 tgacaggatc aaattcacac ataacaatat taaccttaaa tgtaaatggg ctaaatgccc 14820 caattaaaag acacagacta gcaaactgga taaagagtca agacccatct catgtgcaaa 14880 gacatacata ggctcaaaat aaagggatgg aggaatattt atcaagcaaa cggaaagcac 14940 aaaaaagcag gggctgcaat cctagtctct gataaaacag actttaaacc aacaaaggtc 15000 aaaagagaca aagactggca ttacataatg gtaaaggaat caacgcaaca agaagagcta 15060 gctgttctaa atatatatgc acccaataca gaggacccag attcataaag caacttctta 15120 gagacctaca aagagactta gactcccaca caataataat gggagatttt taacaccgca 15180 ctgtcaatat tagatcaacg agacagaaaa ttaacaagga tatctaggac ttggaagtca 15240 cctctggacc aagcggacct aatagacatc tacagaactc tccacctcaa atcaacagaa 15300 tatacattct tcttagcacc acattgcact tattccaaaa ttgaccatat aattggaagt 15360 aaaaaactcc tcagcaaatg caaaagagcg gaaatcataa caaactgtct ctcagaccac 15420 agtgcaatca aattagaact caggattaag aaactcactc aaatccacac aactacatgg 15480 aaactgaaca atctgctcct gaatgactac tgggtacata acgaaatgaa ggcagaaata 15540 aagatgttct ttgaaaccaa tgagaacaaa gacacaacat accagaatct ctgggacaca 15600 tttaaagcag tgtgtagagg gaaatttata gcactaaatg cccacaagag aaagcaggaa 15660 agatctaaaa ctgacaccct aacatcaaaa ttaaaagaac tagagaagca ggagcaaaca 15720 cattcaaaag ctagcagaag acaacaaata actaagatca gagcagaact gaaggagata 15780 gagacacaaa atacccttca aaaaaatcaa tgaatccaga agctggtttt ttgaaaagat 15840 caacaaaaga gatggaccac tagtgagacg aataaggaag aaaagagaga aggatcaaat 15900 agacacaata aaaaatgata aaggggatat caccactgat cccacagaaa tacaaactac 15960 cgtcagagaa tactataaac acctctatgc aaataaacta gaaaatctag aagaaatgga 16020 taaattcctc gacacataca ccctcccaag actaagccag gaagaagtcg aatccctgaa 16080 tagaccaata acaatttctg aaattgaggc agtaattaat agcctactaa acaaaaaaag 16140 cccaggacca ggtggattca cagctgtatt ctaccagagg tacaaacagg agctggtacc 16200 attccttcta aaactattcc gaacaataga aaaagaggga atccccccta actcatttta 16260 tgaggccagc atcatcctgc taccaaaacc tggcagagac accacaaaaa aagaaaattt 16320 caggccaata tcccttatga atattgatgt gaaaatcctt gataaaatac tggcaaacca 16380 aatccaacca agatcaagtt ggcttcatcc ctgggataca aggctggttc agcatacaca 16440 aatcaataaa cataatccaa catataaatg acaaaaatgc catgattatc tcaatagatg 16500 cagaaaaggc cttcgccaat attcagtagc ccttcatgtt aaaaactcaa taactaggta 16560 ttgatggaac atatctcaaa ataataagag ctatttatga caaatccaca gccaatatca 16620 tactgaatgg gcaaaaactg gaagcattcc ctttgaaaat aggcacaaga caaggatgcc 16680 ctctcttagc tctctctctt attcaacaca gtattggaaa ttctggccag ggcaatcagg 16740 caagagaaag aaataaaggg tattcagtta ggaaaagagg aagtcaaatt gtctctgttt 16800 gcagatgaca tgattgtgta tttagaaaac cccatcgtct cagcccaaaa tctccttaag 16860 ctgataagca acttcagcaa agtctcagga tacaaaaatc aatgtgcaaa aatcacaagc 16920 atttctgtac accaataaca gagagtcaaa tcatgagtga actcccattc acaattgcta 16980 caaagagaac aaaatactta ggaataatac aacttacaag ggatgtgaag gacctcttca 17040 aggagagcta caaaccactg ctcaaggaaa taagagagga tgcaaacaaa caaatggaaa 17100 aacattctat gcccatggtt aggaagaacc aatatcgtga aaatggccat actgcccaaa 17160 gtaattatag attcaatgct atccccatca agctactatt gactttcttc acagaattgg 17220 aaaaactact ttaaatttca catggaacca gaaaagagcc tgtatagcca agacaatcct 17280 aagcaaaaag aacaaacctg gaggcatcat gctacctgac ttcaaagtat actataaggc 17340 aacagtaaca aaaacagcat ggtactggta ccaaaacagt tatatagacc aatcaaacag 17400 aacagaggcc tcagaaataa caccacacat ctacaaccat cttgatcttt gacaaacctg 17460 acaaaaacaa gcaatgggga aaggattccc tatttaataa atggtgttgg gaaaactggc 17520 tagccatatg caaaaagctg aatctggatc ccttccttac accttattca aaaattaact 17580 caagatggat taaagattta aatgttaaga cctaaaacca taaaaaccct aaaagaaaac 17640 tcaggcaata ccattcagga cataagcatg ggcaaagact taatgactaa aacaccaaaa 17700 gcaatggcaa caaaagccaa agtagaccaa tgggatctaa ttaaactaaa gagctcctgc 17760 acagcaaaag aaactattag agtgaatagg caacagaatg ggagaaaaat ttgcaatcta 17820 tccatctgac aaagggctaa tatccagaat ctacaaagac cttaaagaaa tttacaagaa 17880 aaaaaaaaca tcaaaaagtg gtcgaaggat atgaacagac acttctcaaa agaagacatt 17940 tatgtggcca acaaacttga aaaaatgctc atcatcactg gtcattagag aaatgcaaat 18000 caaaaccaca ttgagatacc atctcacacc agttagaatg gcgatcatta aaaagtcagg 18060 aaacaacaga tgctagaggg gctgtggaga aataggaacg cttttacact gttggtggga 18120 gtgtaaagta gtgcaaccat cgtggaagac agtgtggcaa ttcctcaagg atctagaact 18180 agaaatacca ttgcacccag caatcccatt actgggtata tacccaaagg attataaatc 18240 attctactat aaaaatacat gcacacgtat gtttactgcg gcactgttca caatagcaaa 18300 gacttggaac caaccaaatg cccatcaatg atagactgga taaagaaaat gtggcacata 18360 tacaccatgg aatactatgc aaccataaaa aagatgagtt catgtccttt gcagggacat 18420 ggatgaagct ggaaaccatc attctcagca aactaacaca agaacagaaa accaaacacc 18480 acatgttctc actcataggt gggagttgaa caatgagaac acatcgccac agggagagga 18540 acatcacgca ctgtggggcc tgtcggggag tggaggaggg atagcattag gagaaatacc 18600 taatgtagat gacggtttga tgggtgcagc aaaccaccat gccacatgta tacctatgta 18660 acaaacctgc atgttctgca cgtgtatccc aaaacttaaa gtataataaa aaaagatgaa 18720 aaaaagtttc aacttgaaat agttcagaaa taaaatactt ttaatcatta agcaatgtat 18780 agttgagttg tatattagtt taatagtaaa ttttactttt caaagtatat actaagtcaa 18840 tgaaatatta gatcatcttt tctctgatat tttttgttat attgctaatg tatggttgtt 18900 tatataatca agatcataac atttcacctt gaattgcata atccagcctt cagtgggagt 18960 caggtcatgg gtcactgcat acacctcccg tccatcatga ctgccacaga gcatcacacc 19020 atcaggggag tcacagaatc tttctactgt acaatcatca tggaatagcc agtgctcatt 19080 cacttaaaac aaaaaaacaa aattttatga caaatttgtg acaaaaatac ttgaagcaaa 19140 ttttcacttt aagcaagaca tagaattatt ttaagtagaa actgctcata ttatatacac 19200 tctatagaca aaacactaat ataaatacat tgtttcagga acataaatac taggaggatt 19260 gagatatatg ccctttgtct gatattagta cacacacaac catagatatt agtctacaca 19320 tgaaaaaaag tatattgtac acattgtaaa tgaaaatcaa aaggaaataa ctaatttttt 19380 gacagatatt taacttttta gatagcatat aaagaagtag agatgatttt taattttaaa 19440 aattttattt acagtgtctc gtttattagg aaagaatcat gaagaatcac aattgcactg 19500 ggctggtcat tttattttat tttttttaat accggatagg gaatagagtt aactactact 19560 cacattctga aagtattatc tgggtaacta aaaagcttgt aatgaatttt ttatagcttt 19620 atcaagatat aactgatata caaaaatgac acacatttaa aacatacatc ttggctgggt 19680 atggtggctc atgcctgtaa tcccagcact ttgaaaggct gaagtgggag gatcgcttga 19740 ggccagcctg ggcaacatag tgagatcctg actgttaaaa aaaaaattag ctggagtggt 19800 ggtgcacgcc catagtctca gctacttagg aggctgcttg agtccaggag ttcagggctg 19860 cagtgatttg tgattgtgcc actgcactcc agcctgggca gcagagtgag accctgtctc 19920 taaaaaattt gttttaaaaa atgaaatata catttgatga ctctggaaat atgcacaacc 19980 catgatacta tcaccacaag cagggcacca aatcgatcca tcacttccaa aaatttcctt 20040 gtattctttt gtgtgtgtgg tttttagttt ttgttggggg gttgctgttt agaacaccca 20100 acaagagaca tatcctctta acatatgttc agtgcacaat ataatcctgt caaccataga 20160 cactatgtca tacagcagat ctctagaact tatttctttt gcatgacaga aactttatag 20220 ctactgaaaa agtattcatt tcccctttct ccagatcctg gcaaccaccc tatttaatta 20280 gataaacaaa tgatttttga gtttaagaaa tgagtttata acaaacttgt tataaaggct 20340 aattttaagt cctataatgt gaagccatgt ttaatttggc caaaagtaaa ataaaatctt 20400 attaaataga ttatttaaga aattaggatt ctaagataat actgttataa atttaccttg 20460 gtaatgttct taatatttga ttatttatgt atggatattc aagtattctg gatagatatt 20520 tcttttaata agtcttgact cctaaacctg attaacagtt aacactttga ggaaatgtac 20580 tcatcaagat actactgaag aaatagattt gaaggtgtct aaagaaaacc taagtagtaa 20640 gactatgaat tgattaatgc agagtacatc ttgtgtgttg atcctctctc tctttctctc 20700 ttaacccctt cctccacaac cctcacagtt ccttttctct tctggaagag atgattttac 20760 attaatttta tcccagaaaa gttagaaatt aaacatatcc ataatatatg ttgcatctca 20820 ttcacagtat gctttgattt tataggtcca attcttttct aaaagtcttc tggctagtcc 20880 cagcatttcc agggaagctg aacaggtgca gccggaggct tggagccact atggaagcag 20940 cacagttgat gcctcagagg atccagagaa aagaccagat aactataatt cagccttcac 21000 ccatattgtg tctttttgat tttgtctgag tatatatgcc gcacaacaag cagcttatct 21060 ctgagattca aatagttact gcaattccat tatctgtttt tttactgtga gggatttgga 21120 gccacattta gtcctacatc acagatacag gactcaagag tcaaagtgca cagaaatttg 21180 aattccgata agaatactct gagccagttt attctggggt acatacttca ttttatgcta 21240 gaactctgca atcctgatga aagagggctt gcattgctca actaactaac tcacccgtct 21300 ctcctgcagt attagaaact acttctgtat gtacacgtta cagtttctag gaactccatt 21360 tttgcaagac agataggagc cagaaaattt gttccttcaa ctgtatatcg ctaattaaac 21420 ataaaatcaa atcagcattt taggtacttg aataactagt ctgtgcttac ttttattcat 21480 atggaagcag tgtttaaatt attctctgat tgtaaactca cttatgtaaa ccattataca 21540 ggaaaaaaat gagtaatgaa gcaaagttct gaagcagatc tatgtaagca aatttcaata 21600 accttcttaa gagaatatga cacttagtag tggtgaggga cattttaagc tttttctatt 21660 tacaagtttt ttttaaacga gggtgtttca aagtaaatat ttgctgttac gttatgccac 21720 atgatatact aataaatgaa ttaatgaaat taacctaaat atccagtatt attattgaat 21780 atatagctac taaaatttta tattcaaata tatccaagga catgaggaaa taaggattta 21840 attctaaaca aaaaaagaag ctatgaaata tatataattt aagactataa ttttgttaaa 21900 aatatgttta tgtaaatgcg ctaaaaaaag ttctttaaga atatatgcca aaatattgac 21960 aatggttatc ccctgagtga tttttatttt catccttagg attttctgta ttttctgttt 22020 cacattttga acatgtatac ttttacaaga aaatatgaac taaaattaaa aatttttaaa 22080 ctcctcaagt ttcaattttt tttttccagg acatgctatt cttctggaag attcttatca 22140 gtcttattat tgtaaaaatg aaccagactg tcttttccat gcaagttgct aggggctgag 22200 ctgggtgtga cagagttcca ctgtctgaat caatactggc ataacagtat atcaatcttt 22260 actatttaga tacatgctag tatgggatat ataatgaata tcactgcttt atctgaagat 22320 accatgtttc atgtagtata acaaatatgt ggcatggcaa agatacatac ttaatataag 22380 acaccacttt ttataaagat gaccagaata gtgtcatgaa atgaaaacaa gacattaaaa 22440 atgagaggag gataggccgg gcatggtggc tcacgcctgt aatctcagca cactgggagg 22500 ccgaggtggg cagatcacct gaggttgggg gttcaagacc agcctggcca acatggtgaa 22560 accccatctc tactaaaatt acaaaattag ctgggcatgg tgtcacatgc ttgtaatccc 22620 agctactctg gaggctgagg caggagaatt gcttgcacct gggaggcgga ggttgcagtg 22680 agctgggatt gtgccattgt actccagcct aggcaacaag aatgaaactg acttaaaaaa 22740 aagagaggag tacaaagagg tccttcctgc ttcaccaata tcattgaata cccctatagg 22800 gaatgaaggg taacaagcaa gacctgggac atgacctaag acatgaaatg ccattacaaa 22860 tgtgtctgcc ctgtagcaaa acacaatatt tgtcttcaga tactaaaaca aatgactggg 22920 aaatgtcatt tgttgggcag aagatttggg tagaaatctt tggctttcta cccaaaatag 22980 aaaacaggaa acactgaaaa ttttctaaga aaagaaaatc ctgttaataa aattatagat 23040 tgctatatat aaaaacacac tagctggctt gaatgaaaga aaagatttag ttaaaatgcc 23100 aactaggaag gctgagagga acaaaaggat gacacccttt tcagcgtttc tacaccactg 23160 gaacatctga aaaggttcca tattttgctc ttttgaaaag acccaaatcc aaaccactgc 23220 atttccactg ggctttttat ttagcgctgt gcataattta cctgaagttt tgtcttccat 23280 aaacatgtca aaggcgatcc tcccgacagg gccggcatct gcaggggagc gctcatgctg 23340 gggtactggg gcgctgctga aggtgtccag cataacggtc ctttggtcag cagagcctga 23400 gatgaggaca ttgtcaatgg cccagtcgtt ctgatccagg ccgtcatgtc ttggctgcca 23460 ccagcggaag cgagtggcaa tctctttagc atcaggaggg agaaggatat tcacaaatct 23520 ataggaaaat gatggggaag ggtgtgggga agaacccttg tcaaatatct tctctgagta 23580 aaagatttac aaccagccat aagataatgt atgtcacatg gtgggtgagg gaaggacata 23640 agctaaaata attttcaaaa accacgatta actggcttaa ttttatgaag tctcagtagt 23700 cactaaattg ggggaaatag aatgtgaaca gattcaagta tcccagaact cccaattggt 23760 tctgtctctg ggcaggcttt agagggactg cacagttttt tgcatacctg gtgggtatct 23820 gtaggcctag agtatatgca ctttggtaga cataagccaa tgctgacttt tttctgtcac 23880 ctagtgcttg gcttcttctg cttccttccc tggcaccttg ttttcactct gtttccatga 23940 gtgctggcaa gtgacttggg gtatggacac tggattgtgg gaggacattt gagttctcag 24000 cctgagggta ccaggtccat tatcagttgt ctgtggtgca gacactgact ttgtttatat 24060 gctttgttga aaatatttaa aattgtatat attcatagaa aatgtcatgt gagaaccatg 24120 ggctagcaag cccagcatgc tatctatccc tgtctcactc accagggaca gacatggaaa 24180 aatgtggctc catgctccaa cagaaaactg aattagctag aaataaggtc taaaatgccc 24240 tttaatcaca attatacatg aaaacccagg aacatatcaa cctcttgaat ttatattcat 24300 aactcataaa atctgttggg gaagataatg tccttagatt taccatcctc ctcacaaagt 24360 atcttttttt tttttttttg agacagagat ctcactctgt tgcccacgct ggagtacagt 24420 ggtacaatct cggctcactg caacctccgc ctcctgggtg caagcaattc tcctgcctca 24480 gcctcccgag tagctgggat tacaggcgcg catgccaaca tgcctggata atttttgtat 24540 ttttagtaga gatagggttt caccatgttg gccaggttgg tttcgaactc ctgacctcgg 24600 gtgatccacc cacctcagcc tcccaaagtg ctgggattac aggcatgagc caccatgccc 24660 agccagtatc atcttatttt tttaatctat gctaatctac ctccctttag aggcatacct 24720 caagggatgc cttttcgtgt ttgcagaact ccaaggcaag acaaccagtc caagttcatc 24780 ccatgaagcc ctttaaactg agggcttcag tgacagtttt agttcttgtc tttcacatta 24840 aagagatttc attatattaa ttttgtttat acagtatctc catgttgatt ttatttttcc 24900 ttcctttttt ttttctgtct tccttgaggt agagtggcca gaacagtagg tagtattcca 24960 gatggaggcc aaccaagatt cactcacagg taggatgctt ttagctggat ttatacaact 25020 tgaattttaa atactttttt ctattatgcc atcattctgt gcgccctttg ggccatgata 25080 gcttaatgga tcttagtctt agggaagaac agtgtagtct agaaagtatc aatcttagac 25140 cctcacctgt gcgggtactg gcagctggga gacatcaccc tttatgcaga gtcttttccg 25200 aagtctattt cctcatttat gtcaattttg aagctcatct gtcttccctg cacctttttt 25260 ttttttggta tgcttatctt gtgagatgtt cctaacattt acctctattg gtttgacatg 25320 tttacatact atccgaaatc tgtcagtttc tgggggacac acaatcgcac ttcttcacac 25380 agagcaatga tcttttatct ctattttttc tttcctaatt ctaaattagt ttttattttc 25440 tctgataagt ctttgaccac attttaaaaa tctctggaat ggaaatttac ctaaggctac 25500 ttgaaagtct aaataaatta taaccacttt tcctacctca gtcaatttga ttccccttca 25560 gagaactaaa gtagattaga cagttatgct tttaccctac agaaacataa ctctcttttc 25620 cttgcactaa cgttatgctg cttaagtgtt caggaactca cacttgaggt ctttataaat 25680 tcctccatca agaccaagga aacagtttac ttggcttgtc tgttatctcc tactaacagt 25740 tgagcacagg gtactctgta ccacttagct tctagttgga ttcctttatt ggtgtccaac 25800 tttaatgcaa gtggaagatt taaaagtttt gcttgtggca aaaactgctg gtatttcctc 25860 agtggccatt ctccctttct tccttcctaa taggagcctt ttcatccaag tgactggtcg 25920 cccagaataa agacagcatg tccagccttc cttgcatctg ggtgtggcta tgtggctaaa 25980 ctcaatagct aatggaatat gaaaggaagt acgtgcagct gttaggaaat gtccttgaag 26040 agagagcaca cccttctcgc cccaatctcc ttcctatgga ctgtaaagtt ggggagctag 26100 tggccctttt ggaccatgag atgaaagtca catgctgagt ggggcagaac aataagacag 26160 gaggaacctg ggtcactggt gcttgcggag ccactacagt agtcctggag tacttttttt 26220 ggggatgtaa tttacatagg agagagagaa aaattaagta attttgtctt tcctgccatt 26280 gacagctgaa cctattctta actgatatat tgaatttaaa tgatcattta taagattctt 26340 tttattttac tcaaatttta gcctgtatct ggcttgcatg cattaaagga ttatctacgt 26400 ttcctttttt tttttttttt ttttttaaag atgcggtctt actctgtcac ccaggctaga 26460 gcatagtgcc acaatcatag cttactgcag cctcaaactc ctgagctcaa gcaatcctct 26520 tgcctcagcc tcctgagtag ctgggactac aggcacatgc caccacaccc aggtaattta 26580 agtttttttt ttttttggta aaatgtcttg ctttgctgcc caggctggtc ttgaactcct 26640 ggcttcaagt gatcctcctg ccttggcttc ccaaagtgct gggattacag gtgtgagcca 26700 ccatgcccag catgtgtttc ctgtctgggc tatatttatt tcctcttctc ttcagcctcc 26760 ccctggaccc tgcctttctc tctctctcat tctttctgtc ttctcttttc ttaccctctt 26820 cctcctccta ctttactgaa tatgctattt tccttcttaa caactctttg acatttctaa 26880 ttggtcataa tcattgcttt cggcccttca gtactttttt taaaatgacc catacgttgt 26940 gtttattcaa ggtttttaaa taaggagttt aaaaataatc tctaggcttc ttaaggatat 27000 ttacatttta ttgtgtttct ttgctttcca gtccaaaatt ctctaaaaac agagtgtaca 27060 ctatataaat aaatatttat ttttctgttt ccattttccc aaagcattgc tgaaattaat 27120 tatactagtt aatttctgtg ggtttttgca ctgggtttat tcaccgttgg cattgtggta 27180 gaatatttca tcttattctg ggatgtgaaa actagttgtt cttaaaataa aaacccaaac 27240 cagctattta tccagctcag aaacccttct tcatttcagt ctcagaggca tcctctagtg 27300 aggcataagt ctgaggtccc cctcagtctc ccgtgactga ttgctggtag caatctctgc 27360 tcgatgtact cgttattaga tatcaaatcg aatacaaacc cgggcttact gtactggtca 27420 tagaaaatct ccatgagcag gttccaggta atgcctccat tgacagaata ttccaagaga 27480 acaccttggt tacggttgtt tggtgtaatc aggcacccat acatgaagta aaattggatg 27540 aactcagcat tagtgaggtt tagatccaca gtgactaata atcgactaca accctaagaa 27600 aaagaagtaa aataaaaaaa agtgataagg aatctcgatt gcagattata gattttctat 27660 ggattttttt tttttttgag acagggtctt gctctgtcac ctaggctgga gtgcagtggc 27720 accatcacag ctcactgcag ccttgacctc ctgggttcaa gtgatcctcc cacctcagcc 27780 tcccaagtgg ctgggactac gggtacatgc ctccatgtct agctaatttt ttgtagagac 27840 agggttttgt tatgttgtcc aggctggtct taactcctgg gctcaaatga tctgcctgcc 27900 tcggcctccc aaagtgctgg tatttccatt cttttaatat ttattttgtg ataccagcca 27960 catagtattg tggcactgat tttcttaccc tctttcttac tatgctagct cttagtattt 28020 tgcctagtac acagtaggta cccagcacat gtttgctgaa ctttgaaatt tcagcattca 28080 agacttattt acagagaaca atgtattcca agataatttt ctgttttctt tttccttttt 28140 tttaatatga atgtttattt gggccaaggt tgagtatcgc agcccaggac acatttccaa 28200 gttgccttgg ctgttttttt ttcataagca agatgagagc tggaactaat ataactgtcc 28260 tttattttta ttaaactatc tccagttatt ttcagacact attagatttt taaaaatgaa 28320 tcaaccacta agaaaatagc atattgagat gaccatttta ttatgattat tattatttaa 28380 ttttttgaga cagtctggct ggagtgcagt ggtgcagtct cggctcactg caacctccat 28440 ctcctgggtt caagtgattc tcttgcctcc gcctcccgag tagctgggac cacagttgtg 28500 tgctaccaca cccggctaat ttttgtattt ttaatggcga tggggtttca ccatgttggc 28560 caggctggtc ttgaactcct gacctcaggt gatctgccca cctcggcctc ccaaagtgct 28620 gggattacag gcgtgagcca ccgcgcctgt aaatagatga ctattttaat atgaaattta 28680 aaaatagcta catctggaaa ttttataatt atacagataa tctaattact gtaatgtttt 28740 aaattcacac tttagcagaa tttaatggca tctgtattaa tttcttaatg ttgatatacg 28800 gatttttttt agttgaacat atgtgaaaaa ctcactttta gttctaagtg aggaaaagta 28860 tcctgaacac tgcagtcttt ctcagtgttg ctgattataa aaagcctaca tgctatatgc 28920 cttcttgcta ctcgagctaa aatgttgaat ataaataata cacttcattg gcacaaatgt 28980 aaactctaag gtagggcatg ctaaggaaat aaagagctgg cagtaaattt gttatttttt 29040 tttttttttt tttttttttt ttttgagacg gagtctcgct ctgtcgccca ggcgggactg 29100 cggactgcag tggcgcaatc tcggctcact gcaagctccg cttcccgggt tcacgccatt 29160 ctcctgcctc agcctcccga gtagctggga ctacaggcgc ccgccaccgc gcccggctaa 29220 tttttttttg tatttttagt agagacgggg tttcaccttg ttagccagga tggtctcgat 29280 ctcctgacct catgatccac ccgcctcggc ctcccaaagt gctgggatta caggcgtgag 29340 ccaccgcgcc cggccaaatt tgttatttta aaacattaat ttgtctatct aatcatggta 29400 tacaagaaat tgtattttaa acagagtcgc ctttggcaga aaagtagagt gactataaaa 29460 tttcccaaag aaagtttcca agctt 29485 7 19 DNA Pres-specific Primer, sense 7 tacctcacgg agccgctgg 19 8 21 DNA Pres-specific primer, antisense 8 gcagtaatca gtccgtagtc c 21 9 22 DNA Cyclophilin Primer, sense 9 tggcacagga ggaaagagca tc 22 10 22 DNA Cyclophilin primer, antisense 10 aaagggcttc tccacctcga tc 22 11 780 PRT Rattus norvegicus 11 Met Ala Ala Arg Asp Arg Arg Ser Glu Pro Pro Gln Leu Ala Glu Tyr 1 5 10 15 Ser Cys Ser Tyr Ala Val Ser Arg Pro Val Tyr Ser Glu Leu Ala Phe 20 25 30 Gln Gln Gln Arg Glu Arg Arg Leu Pro Glu Arg Arg Thr Leu Arg Asp 35 40 45 Ser Leu Ala Arg Ser Cys Ser Cys Ser Arg Lys Arg Ala Phe Gly Ala 50 55 60 Leu Lys Ala Leu Leu Pro Ile Leu Asp Trp Leu Pro Lys Tyr Arg Val 65 70 75 80 Lys Glu Trp Leu Leu Ser Asp Ile Ile Ser Gly Val Ser Thr Gly Leu 85 90 95 Val Gly Thr Leu Gln Gly Met Ala Tyr Ala Leu Leu Ala Ala Val Pro 100 105 110 Val Gln Tyr Gly Leu Tyr Ser Ala Phe Phe Pro Ile Leu Thr Tyr Phe 115 120 125 Val Phe Gly Thr Ser Arg His Ile Ser Val Gly Pro Phe Pro Val Val 130 135 140 Ser Leu Met Val Gly Ser Val Val Leu Ser Met Ala Pro Asp Asp His 145 150 155 160 Phe Leu Val Pro Ser Gly Asn Gly Ser Thr Leu Asn Thr Thr Thr Leu 165 170 175 Asp Thr Gly Thr Arg Asp Ala Ala Arg Val Leu Leu Ala Ser Thr Leu 180 185 190 Thr Leu Leu Val Gly Ile Ile Gln Leu Val Phe Gly Gly Leu Gln Ile 195 200 205 Gly Phe Ile Val Arg Tyr Leu Ala Asp Pro Leu Val Gly Gly Phe Thr 210 215 220 Thr Ala Ala Ala Phe Gln Val Leu Val Ser Gln Leu Lys Ile Val Leu 225 230 235 240 Asn Val Ser Thr Lys Asn Tyr Asn Gly Val Leu Ser Ile Ile Tyr Thr 245 250 255 Leu Ile Glu Ile Phe Gln Asn Ile Gly Asp Thr Asn Ile Ala Asp Phe 260 265 270 Ile Ala Gly Leu Leu Thr Ile Ile Val Cys Met Ala Val Lys Glu Leu 275 280 285 Asn Asp Arg Phe Lys His Lys Ile Pro Val Pro Ile Pro Ile Glu Val 290 295 300 Ile Val Thr Ile Ile Ala Thr Ala Ile Ser Tyr Gly Ala Asn Leu Glu 305 310 315 320 Ala Asn Tyr Asn Ala Gly Ile Val Lys Ser Ile Pro Ser Gly Phe Leu 325 330 335 Pro Pro Val Leu Pro Ser Val Gly Leu Phe Ser Asp Met Leu Ala Ala 340 345 350 Ser Phe Ser Ile Ala Val Val Ala Tyr Ala Ile Ala Val Ser Val Gly 355 360 365 Lys Val Tyr Ala Thr Lys His Asp Tyr Ile Ile Asp Gly Asn Gln Glu 370 375 380 Phe Ile Ala Phe Gly Ile Ser Asn Val Phe Ser Gly Phe Phe Ser Cys 385 390 395 400 Phe Val Ala Thr Thr Ala Leu Ser Arg Thr Ala Val Gln Glu Ser Thr 405 410 415 Gly Gly Lys Thr Gln Val Ala Gly Leu Ile Ser Ala Val Ile Val Met 420 425 430 Val Ala Ile Val Ala Leu Gly Lys Leu Leu Glu Pro Leu Gln Lys Ser 435 440 445 Val Leu Ala Ala Val Val Ile Ala Asn Leu Lys Gly Met Phe Met Gln 450 455 460 Val Cys Asp Val Pro Arg Leu Trp Lys Gln Asn Lys Thr Asp Ala Val 465 470 475 480 Ile Trp Val Phe Thr Cys Ile Met Ser Ile Ile Leu Gly Leu Asp Leu 485 490 495 Gly Leu Leu Ala Gly Leu Leu Phe Gly Leu Leu Thr Val Val Leu Arg 500 505 510 Val Gln Phe Pro Ser Trp Asn Gly Leu Gly Ser Val Pro Ser Thr Asp 515 520 525 Ile Tyr Lys Ser Ile Thr His Tyr Lys Asn Leu Glu Glu Pro Glu Gly 530 535 540 Val Lys Ile Leu Arg Phe Ser Ser Pro Ile Phe Tyr Gly Asn Val Asp 545 550 555 560 Gly Phe Lys Lys Cys Val Lys Ser Thr Val Gly Phe Asp Ala Ile Arg 565 570 575 Val Tyr Asn Lys Arg Leu Lys Ala Leu Arg Arg Ile Gln Lys Leu Ile 580 585 590 Lys Lys Gly Gln Leu Arg Ala Thr Lys Asn Gly Ile Ile Ser Asp Val 595 600 605 Gly Ser Ser Asn Asn Ala Phe Glu Pro Asp Glu Asp Val Glu Glu Pro 610 615 620 Glu Glu Leu Asp Ile Pro Thr Lys Glu Ile Glu Ile Gln Val Asp Trp 625 630 635 640 Asn Ser Glu Leu Pro Val Lys Val Asn Val Pro Lys Val Pro Ile His 645 650 655 Ser Leu Val Leu Asp Cys Gly Ala Val Ser Phe Leu Asp Val Val Gly 660 665 670 Val Arg Ser Leu Arg Met Ile Val Lys Glu Phe Gln Arg Ile Asp Val 675 680 685 Asn Val Tyr Phe Ala Leu Leu Gln Asp Asp Val Leu Glu Lys Met Glu 690 695 700 Gln Cys Gly Phe Phe Asp Asp Asn Ile Arg Lys Asp Arg Phe Phe Leu 705 710 715 720 Thr Val His Asp Ala Ile Leu Tyr Leu Gln Asn Gln Ala Lys Ser Arg 725 730 735 Glu Gly Gln Asp Ser Leu Leu Glu Thr Ile Thr Leu Ile Gln Asp Cys 740 745 750 Lys Asp Pro Leu Glu Leu Met Glu Ala Glu Ile Asn Glu Glu Glu Leu 755 760 765 Asp Val Gln Asp Glu Ala Met Arg Arg Leu Ala Ser 770 775 780 12 20 PRT Synthetic Peptide from N-terminus of Prestin 12 Met Asp His Ala Glu Glu Asn Glu Ile Pro Val Ala Thr Gln Lys Tyr 1 5 10 15 His Val Glu Arg 20 13 22 DNA Primer for PCR amplification of C-terminus of prestin 13 gccctgaatt cctcgggtgt gg 22 14 21 DNA Downstream Primer for C-terminus amplification 14 ggactacgga ctgattactg c 21 15 22 DNA Primer for prestin N-terminus amplification 15 ctgcagaatt cggatcatgc cg 22 16 22 DNA Upstream Primer for N-terminus amplification 16 caacgatggc tatggcaatg gc 22 

What is claimed is:
 1. An isolated polynucleotide comprising a portion which anneals with high stringency with at-least twenty consecutive nucleotide residues of a coding region of a mammalian pres gene.
 2. The isolated polynucleotide of claim 1, wherein the mammalian pres gene comprises a nucleotide sequence selected from the group consisting of SEQ ID NO: 2 and SEQ ID NO:
 4. 3. An isolated polynucleotide comprising a portion which anneals with high stringency with at least twenty consecutive nucleotide residues of a coding region of a mammalian pres gene, wherein the coding region is one other than a coding region which corresponds to any of exons 1-6 of the human pres gene.
 4. An isolated polynucleotide which comprises the coding region of a mammalian prestin gene, wherein the coding region of the gene is at least 75% homologous with the coding region of at least one of the gerbil prestin gene and the murine prestin gene.
 5. The isolated polynucleotide of claim 4, further comprising a promoter/regulatory region operably linked with the coding region.
 6. An isolated mammalian prestin protein.
 7. The isolated protein of claim 6, wherein the mammalian prestin protein is isolated from a mammal selected from the group consisting of a gerbil, a mouse, and a human.
 8. The isolated protein of claim 6, wherein the protein has an amino acid sequence selected from the group consisting of SEQ ID NO: 1 and SEQ ID NO:
 3. 9. The isolated protein of claim 6, wherein the protein is substantially purified.
 10. An isolated antibody which specifically binds with a mammalian prestin protein.
 11. A method of alleviating a hearing disorder in a mammal afflicted with the disorder, the method comprising providing a mammalian prestin protein to cochlear outer hair cells of the mammal, whereby the disorder is alleviated.
 12. The method of claim 11, wherein the protein is provided to the cells by providing to the cells a polynucleotide encoding the protein.
 13. A method of rendering the surface area of a lipid bilayer susceptible to modulation by membrane potential, the method comprising providing a mammalian prestin protein to the bilayer, whereby the bilayer is rendered susceptible to modulation by membrane potential.
 14. The method of claim 13, wherein the lipid bilayer is the plasma membrane of a cell.
 15. The method of claim 14, wherein the protein is provided to the bilayer by providing a polynucleotide encoding the protein to the cell and expressing the protein in the cell.
 16. A method of modulating the surface area of a lipid bilayer, the method comprising providing a mammalian prestin protein to the bilayer and thereafter modulating the membrane potential, whereby the surface area of the bilayer is modulated.
 17. A method of modulating the stiffness of a lipid bilayer which surrounds a relatively fixed volume, the method comprising providing a mammalian prestin protein to the bilayer, and thereafter modulating the membrane potential, whereby the stiffness of the bilayer is modulated.
 18. A method of modulating the volume of a porous bilammelar lipid vesicle, the method comprising providing a mammalian prestin protein to the bilayer, and thereafter modulating the membrane potential, whereby the volume of the vesicle is modulated.
 19. A method of generating a force between two surfaces, the method comprising interposing a structure which comprises a lipid membrane comprising prestin and enclosing a relatively fixed volume of fluid between the surfaces; restraining the ability of the structure to expand in a direction at least partially parallel to at least one of the surfaces; and altering the membrane potential of the lipid membrane, whereby the structure impacts upon the two surfaces and a force is generated therebetween.
 20. A method for creating an electrical impulse, said method comprising applying an external mechanical force to prestin, thereby creating an electrical impulse. 